Expensive Gas in CaliforniaIt's Summer and I love going on
Road Trips. It's this time of the year when I drive the most. Due to the recent hike in gas prices, I thought it might be a good idea to share this article with you. Even though gas prices don't hurt my bottom line that much, I can truly feel the pain this must cause a lot of people. As a student I didn't have a lot of money and the cost of gasoline was always a major issue for me. I have learned many ways of saving money for gas by improving my gas mileage. There are many things you can do, aside from going out and buying a more fuel efficient car, that will help you tremendously to cut down your gasoline expenses. Many require only minor adjustments to your driving style. I am going to review some well known techniques and some of my own that I used as a student. I have always been able to exceed the specified gas mileage of my car (even meeting the specified numbers is pretty tough). In my last
article on gas prices, I speculated that those high prices are here to stay and that we will never see really cheap gas again. In this article I am going to talk a bit about what you can do to save gas.
Changing your Driving Habits
Brake the right way
1. A car consumes most gas as it accelerates. It's a simply law of physics (force equals mass times acceleration). A moving car doesn't require much gasoline to keep moving (due to the inherent inertia). In real life this means, in order to improve your mileage you need to keep the ride smooth. Let me give you some examples.
About 30% of the drivers I see in somewhat heavy traffic apparently cannot control their speed with the accelerator pad alone. Instead I see those guys speed up and slam on the brakes all the time. Obviously, that makes the guy following too close behind very nervous and he too needs to brake and accelerate constantly. In really heavy (but still moving) traffic about 90% of the cars do this. It is relatively easy to hold a speed in a long line of cars without stepping on the brake. Just keep a little bit more distance and try to practice this. If the traffic moves along, you rarely need to brake, unless everything slows down. If you pay attention to the cars ahead of you (not just the one right in front of your nose, but the other cars ahead of that one), you can anticipate when things will slow down and you can ease off the gas. This means you won't lose all that power to friction (on the brakes) and you can keep your speed without having to accelerate. In heavy traffic this is the most efficient way to save gas and can easily get you 10% - 20% better gas mileage.
Hybrid drivers
2. If you own a hybrid powered car, the statement above applies even more to you. Try to avoid fast braking. Hybrid cars have the ability to convert braking power into electric energy and store them in their batteries. However this (induction) will only give yo so much braking power. If you need to decelerate faster, your brakes will engage and energy will be lost.
So the next time you are approaching a traffic light, start braking a lot sooner and don't slam on the brakes the last minute. This will significantly improve the efficiency of your hybrid car.
By starting to decelerate sooner, I can often avoid coming to a complete stop (regular car), before the traffic light switches to green and the cars in front of me start rolling. This way I can keep some of my inertia and don't have to accelerate as much (<- more gas saved).
Turn off your air condition
3. This tip might be somewhat impractical in some areas. I would never dare to switch off the air condition of my car in
Arizona in the Summer. However I also know that the compressor for the air conditioner loads the motor of my car more, which will reduce my fuel economy. I try not to use the air conditioner if I don't have to.
Park your car in the shade if you can, so you won't have to keep the AC working as hard when you go somewhere.
Roll down the windows just a tiny bit, so the air can circulate through your car while you are parked (might not be a good idea in areas with a high theft rate).
Turn off the AC 5 minutes before you reach your destination and don't keep it working until the last second.
Shifting Manual
4. A manual transmission is truly fantastic. I can only encourage everyone to try it out. You can pretty much determine if you want a sporty shifting (at higher RPM) or a fuel efficient shifting (at low RPM). No matter how "intelligent" automatic transmissions are, they aren't as smart as you. Due to the way an automatic transmission shifts, there are also higher losses associated with automatic transmissions. Overall a manual transmission can be a lot more fuel efficient.
If you have a manual transmission and want to save some gas, you need to shift up early and shift down late.
Most people get taught that they need to shift at a certain RPM, which is, excuse me, complete BS. You need to feel the car and the load condition to figure out when you need to shift. A car that goes uphill needs to pull a lot more and should be driven at a higher RPM (or else it jumps). On the other side, if you are gliding along an empty road, you can drive at extremely low RPM (high gear). Then if you want to accelerate (you need a bit more power), you quickly shift down, get up to speed and shift up again. I always shift by feeling the car and I rarely ever look at the RPM (except for my amusement or out of boredom, or if I really want to race and need to shift before the red line).
Shifting Automatic
5. If you have a cruise control and there isn't a whole lot of traffic, you probably should use it (it will keep the speed constant and hence doesn't need to accelerate).
6. Use the overdrive gears, as this will generally keep your RPM down and your wallet happy.
7. Shift into neutral when you are standing still to reduce transmission strain and cool off the transmission.
I added some more information on shifting, down in the comments below this post.
Reduce weight
8. Coming back to the force equals mass times acceleration. We already established that one shouldn't accelerate as much. You can also try to reduce the mass of your car by emptying out the trunk and removing heavy items that you don't need (keep your spare tire and car lift, but get rid of the gardening equipment).
Turn your car off
9. When you turn on a car, it uses a bit of gas. When the car is idling, it uses a fixed amount of gas over a period of time (especially with the AC on).
In most scenarios (depending on the car), the energy balance will be positive if you turn off your car for more then 20 seconds.
That means you can save gas if you turn off you car while waiting at long traffic light sequences, railroad crossings or while your better half pulls money from the ATM. Any time you can foresee that you will not be moving for more then 30s or 1minute you should turn off the engine to help your vacation budget.
Drive slower
10. Yeah right. Obviously thats not something I am all that fond off being the leadfoot driver I am. Well, it's a proven fact that driving fast will increase the drag (turbulence) and thus increase your fuel consumption, however I simply cannot bring myself to drive below the legal speed limit. It's your choice. There is not that much difference between 60mph and 65mph in terms of fuel consumption. However I grew up in
Germany (no speed limits). A car racing along at its maximum speed of 200km/h (depending on the car), would consume about twice as much gas as if it were driven at 160km/h. At the upper end of the power spectrum engines become very inefficient.
Ride the slipstream
11. This driving technique has given me some excellent mileage when I used to commute long distance a long time ago. Obviously, it requires a bit of skill and it's not exactly recommended, since you should pay attention to the road and we all know, most people who read this just don't. However it is probably one of the best "secret" fuel saving tips I can give you.
This technique is frequently used by race car drivers to gain speed and truck convoys to save fuel.
Every car has a certain amount of drag (or wind resistance). This drag, the rolling resistance of your tires (see below under maintenance) and the friction in your engine are the three main causes of reduced efficiency. A car moving through the air causes the air to split around the car and turbulence behind the car (the slipstream). If you drive your car into another cars slipstream, both cars will save fuel (less turbulence). The following car saves the most gasoline.
Now remember, I am not advocating to tailgate. However, you can try to find a large truck (more turbulence and a longer slipstream tail) and slip in there. Now you can still keep some distance (unlike the NASCAR driver) and still save gas.
However, many people cannot regulate their speed without braking (see above). In this case you are probably better off just keeping your distance and not braking.
Close your windows
12. Believe it or not, but opening your windows will increase the turbulences and eventually cost you fuel. If you can, use only the ventilation system of your car. I cannot really gauge this against using the air conditioner. I believe that opening your windows at low speeds and using the air conditioner at high speeds gives you better fuel economy.
Fill up at Arco
13. Year after year Chevron and Shell are making new record earnings while squeezing the poor motorists for every penny. They advertise their expensive gasoline with buzzwords such as Techron, V-Power and some other BS words. Basically, that means they put some expensive stuff into the gas to sell it at a better profit. In fact, the gasoline of all gas stations flows through the same pipeline and the only difference is the magic stuff they poor into the gas to claim a cleaner burning fuel or better fuel efficiency. At the same time their average gas price is about 10c - 30c above other cheaper gas stations in the neighborhood. I can see no difference in my gas mileage when I empty a tank of Arco vs. a tank full off Techron enhanced souped-up high tech additive gas spritz. And if it cleans anything then certainly my wallet, which is all squeaky clean after filling up.
Well, I am tired of financing the billions of those mega empires. I am getting my gas at the Arco and I have never had any trouble with the quality. Of course you are free to throw your hard earned dollars at Chevron (pay 10% more and save 3% on their rebate cards - another scam to tie the customer to their high priced gas) or Shell in the hopes their magic bullet fuel additives do anything for you.
Now let me back up a second. Sometimes I actually go to Chevron to fill up. I put exactly 8 gallons into my tank so I qualify for a discount at the car wash.
14. When I am on the road, I try to keep an eye open for gas prices along the way. If I see the price jumping down, i usually fill up. Some gas stations offer free coffee with fill up or a free hot dog, and if their gas costs the same as the gas across the street, I go for the coffee with my gas.
Pick a better route
15. Avoid heavy traffic and lots of traffic lights. The shortest route is not always the most fuel efficient if you have to stop a lot.
Cheap Car maintenance
Why cheap car maintenance? I don't believe that spending a lot of money on fuel additives or special tires or whatever I see suggested elsewhere will really help you to improve your bottom line, and that's what this article is about. For instance I do not believe that your fuel economy suffers much if you change your oil every 5000 miles instead of 3000 miles (but it does save money not to change oil that often).
Pump it up
16. Inflate your tires to the specified level (I usually go about 0.2 PSI above). This will reduce the contact area of your tire to the road and therefore reduce the friction. It will help you to get a slightly improved gas mileage.
17. If you don't need Snow Tires or Chains, remove them. Don't drive around all summer with Snow Tires. They are softer and have a deeper profile which will increase friction.
Rent a smaller car
18. Remember that mass and acceleration equation? Well, a small car always has a better fuel economy due to its smaller mass. Smart budget travelers therefore rent smaller cars and don't care much about the status a shiny big car conveys. They rather indulge in a good drink at the end of the day (when they don't need to drive anymore) with all the gas money they saved. Their vacation pictures look just as glorious, but they still have pocket change for bigger prints.
Reduce drag
19. Why are you driving around with that ski-, bicycle- or luggage-rack on your roof if you don't need it? Didn't you know that this increases the wind resistance of your car? Well now you do. Seriously, removing those will save you quite a bit of gasoline.
Eco tuning
20. Chip tuning for your engine used to be pretty big way back when gas cost less then water. These days the buzzword is
eco tuning. Many tuners offer replacement chips for your engine computer that increase the power while at the same time saving gas. How is this possible? Well to cut this already long article short, they improve both ends of the curve. At the upper end they give you more power (with reduced efficiency) and at the lower end a better efficiency. You choose with the gas pedal which mode to use. Make sure you use manufacturer approved tuners if you don't want to lose your warranty.
Use the correct grade of motor oil
21. The grade of the oil pretty much tells us about the viscosity. If you use the wrong grade, you may increase the friction in your engine. It gets hotter and uses more gas.
Air filters
23. Replace your air filter when you need to, or your mix won't be right. However don't replace it every time the mechanics tell you to (they make money with it). Try to find out how often you need a new filter.
Turn off the lights
24. Well, this one might be a safety concern. Many
Rental Car companies have daylights enabled on their cars which are rather efficient. However every electrical equipment is powered from the alternator which will increase its load on the engine to produce more power. So when you can do it safely, turn off those headlights.
Drive less
Here comes the discussion we don't like to read as much.
Carpool
25. Well, if two people are riding in a car, the gas used per person is immediately cut into half. If 4 people are sharing a ride, their individual gas bill becomes only one third. Since they can now use carpool lanes, they won't have to spend as much time in traffic (idle engines use gas too) and get an even better gas mileage, plus they get home sooner. Its not always feasible though.
Combine Trips
26. Try to combine trips. If you live outside of town, try to go into town only once and get everything you need done.
Fuel Efficient Cars
27. If you are in the market for a new car, you definitely should consider fuel efficiencies. However I wouldn't buy a hybrid just for the better fuel economy if I weren't in the market for a new car. You can easily calculate how much money you would save a year and weigh that against the cost of the car (plus the potentially higher maintenance cost).
28. Its not commonly known, but Diesel engines can give you a much better gas mileage than Hybrids on long distance drives. That's one of the reasons, hybrids aren't popular in Europe but Diesels are.
Bonus:
29. Don't fill up unless you are on empty, since all this gas weighs a lot and as we have already learned (force equals .... - you know it). However I usually only do this when gas prices are falling or constant (so I can wait longer and get cheaper gas). When gas prices are rising, I fill up sooner. Due to the psychological impact of rising gas prices, people usually do the exact opposite, which will eventually cost them more.
30. The list still grows. Someone made an excellent suggestion for trucks in the forum. Dropping the tailgate of his small truck, Ronald is able to improve the aerodynamics and thus get a better gas mileage. Sounds plausible.
31. I also noticed that the first gas station you encounter after a long thirsty stretch is almost never the cheapest. After you leave a national park and didn't have a chance to pump gas for a long time, the first station will often have slightly higher prices as everyone pulls over to fill up as soon as they can. I usually drive a little further to find a cheaper station.
32. I do not fill up on gas stations visible from the Interstate I am driving on or from the main freeways. I usually take an exit at a moderately sized city when I am on a road trip and head for the city center. Before I actually get there, I usually find much better deals. Location and Competition are the factors that determine local price fluctations. This means you need to look for places with lots of competition (hence moderately sized city) and avoid prime locations (get away from the main roads). Large cities often have higher gas prices and are harder to navigate. On my last trip, I pulled over whenever I saw a station that had significantly lower prices then I had seen previously, even if my tank was only half-empty. On road trips, the rules are slightly different. Fill up whenever and wherever it is cheap and do not wait for yout tank to be empty.
Book 3+ nights at Expedia and get a free $50 gas card! - Offer good Monday - Friday until June 30th. 
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Just saw it in the News Yesterday:
33: Make sure your Fuel Cap is o.k. In the US every year 147 Million Gallons of Fuel are lost due to evaporation.
And some more from me:
34: When you park your car in the shade, you also reduce the amount of fuel that evaporates.
35: Don't top off, especially in the summer. The Gas is stored underground where it is cool. When you top off, some gas will spill out of your tank as it warms up.
And that one I completely forgot to mention in the article, but it is one of the most effective gas savings tips:
36: When you drive a car with manual shift and you are on a slightly downhill slope, put it in neutral and let it roll. Your RPM will be at idle while you still make good time. However, please don't try this on a steep slope. Your car might pick up too much speed and it will become hard to control. You might even want to put it in lower gear (to use the braking power of the engine). The car still will hardly use any gas (unless you step on the gas pedal).
For automatic cars, I usually just take out the overdrive to use the engine for braking (saves brake pads).
Edit: Evaporation is probably less of an issue in modern vehicles:
Discussion further down
Actually, in a manual, on a downhill, shifting into idle will burn more gas than leaving it in gear (assuming the hill is steep enough that the engine doesn't slow you down). With your foot off the gas pedal, it is gears and gravity keeping the engine running; there is no fuel going in, only air. If the engine is idling, fuel is being used to keep it running.
Note that on really long hills, engine braking the whole way down *might* trip the O2 sensor in the exhaust system from all the unburnt, clean air running through. Be sure to blip the gas every so often.
Additionally, to point #4, shifting up early can actually result in poorer gas mileage. For example, in my truck, the engine's most efficient point is at 2000rpms; if I shift at or under 2000 rpms, it sort of bogs the engine down. I get the best gas mileage if I run it up higher. However, I don't run it up quickly, with the pedal mashed to the floor, but gently. If you pay attention to the noise of your engine, you should be able to tell how much pedal is just right. There are fanatical drivers who drive barefoot with just their big toe on the gas pedal so they can precisely modulate how much fuel the computer is trying to inject.
Thats why I wrote about light sloping hills. I can see why this is confusing. What I meant was to shift into neutral on slopes that otherwise wouldn't keep the car rolling (very gently sloping hills). You are absolutely right, no fuel is being burned unless you step on the gas.
About #4: It is somewhat hard to describe the concept of load to the engine in an article such as this. Basically you can shift early when there is very little load (straight or downhill) but you should shift later if there is load (uphill, trailer on car). After some practice most people will "feel" when to switch. Forget about the RPM.
That's just stupid and dangerous advice - in order for it to result in a significant increase in fuel efficiency, you'd have to be close enough to risk getting sucked in to to the back of the truck you are following.
Perhaps an even better way to cut your gasoline costs is to purchase an electric vehicle.
The ZAP Xebra Sedan - 4 passengers, 40mph, 25 mile range http://www.zapworld.com/ZAPWorld.aspx?id=188
The Meyers NmG - 1 passenger, 75mph, 30 mile range http://myersmotors.com/index.html
The Commuter Cars Tango - 2 passengers, 150mph, 160 mile range http://www.commutercars.com/
The Phoenix SUT - 5 passengers, 95mph, 100 mile range, 10 min charge http://www.phoenixmotorcars.com/
And for the really high end you could go for the Tesla
The Tesla Roadster - 2 passengers, 130mph, 250 mile range, 0-60 in 4 sec http://www.teslamotors.com/index.php
Or you could always do a conversion of an existing gasoline car like the guys at http://www.evalbum.com
With an automatic I can tell you that you are definitely better off shifting into neutral on almost all hills. I have rented several cars with the fuel economy meter and when I am coasting in neutral when appraoching a stop sign or red light the meter pegs high at 99 MPG. I frequently coast a half a mile in neutral while everyone around me is wasting gas with their foot on the accelerator. I have a 2004 Mazda 6 Sport Wagon with a 3.0 liter V6 and a 5 speed automatic. The new estimates for this car are 24 MPG highway. I average over 31 MPG with just a few tricks. From a standstill I start off in 2nd gear because 1st is just way to low for normal driving. I manually shift to keep the tach below 2000 RPM. When I shift into 4th I put it back in drive because the torque converter will lock up in 4th only in drive and this lowers the RPM's more than shifting into 5th. I watch traffic carefully and shift into neutral and coast when traffic slows or a light changes to yellow. I rarely ever come to a complete stop. On the highway I lock the cruise control on 55. These techniques have given me several tank averages of 32.5 and 32.96 MPG.
If the engine is running, fuel IS being consumed. If no fuel were being burned, there would be nothing for the spark plug to ignite, and the engine would die. The comments about nothing but air being sucked into the engine, and about the o2 sensor are complete utter total BS. Going down a hill in or out of gear in a manual transmission will use just about the same amount of gas. The downside to coasting is increased wear on your brakes. If you REALLY want to save gas, and have a car that will not lock the steering wheel when you do it, and you don't mind manual brakes and steering, just turn the key back one notch til the engine shuts off. Highly illegal, but the best way to save gas on a long downhill stretch.
The most efficient transmission is the continuously variable transmission (CVT). I know they have it on the Toyota Prius, and as option on the Mini Cooper. It basically holds the engine at it's most efficient RPM, and varies the gear ratio to accelerate, and decelerate (there aren't actually "gears" though). This is even more efficient than a manual transmission.
Nothing to add here. I completely agree with this.
This assumes a steep hill where you need to brake or use the motor brake. However I was referring to a gentle down slope, where a car in gear would stop, while a car in neutral keeps rolling. I should have made this more clear.
Don't EVER put your live and the live of others in dager for a few drops of gas (a few cents).
Although the steering wheel won't lock (the key is in the ignition), it will become very hard to steer (no aid) and very hard to brake. There is a reason this is illegal. A slight curve and you might be history.
Yes, completely agree, however its expensive (see number 27).
Very good tips mike. I couldn't agree more, except with the 55mph thing.
It does help to save gas (you pretty much proved it) but it doesn't bother me to get a lower gas mileage when I drive faster.
I HIGHLY disagree with the fill up at arco statement. Yes, gas may come from the same pipeline as all of the other expensive ones. But there is a reason why the name brand gas companies are more expensive than arco.
One word: Additives. Gas that comes from the tanker is the same. You wont find anything different from one tanker to the other. What is different is the packet of addtives that is added to the underground tanks when they are filled up.
Arco uses the bare minimum of cleaning additives required by federal regulations. In the long term, this could be catastrophic to your engine. Sure, you may save a few dollars every time you fill up, but that will all go towards the engine rebuild when you start knocking and pinging due to the lack of additves that keep your valves and upper cylinder clean.
What makes your engine knock? It is the carbon residue that is deposited from lack of cleaners. After the "bang" cycle, the carbon deposits on your vavles become super heated, and the essentially glow red hot. So when your engine sucks in more fuel, and compresses it, that super heated carbon ignites the fuel before the spark plug does, resulting in pre-ignition. this is very bad for your engine.
So to conclude, filling up at arco is not ideal, and could be very bad for you engine if you plan to keep filling with arco for the life of the car.
30: Make sure your Fuel Cap is o.k. In the US every year 147 Million Gallons of Fuel are lost due to evaporation.
And some more from me:
31: When you park your car in the shade, you also reduce the amount of fuel that evaporates.
32: Don't top off, especially in the summer. The Gas is stored underground where it is cool. When you top off, some gas will spill out of your tank as it warms up.
Today's vehicles are equipped with a EVAP system. that evaporating gasoline that comes from your tank is collected inside a charcoal canister, which is then sucked clean by the engine's vaccum system every time you run it.
The evaporating statement may have been true 50 or so years ago when gas tanks were vented into the atmosphere. But current clean air regulations do not allow gasoline to be vented into the atmosphere.
This is 99% true. The newest engines that have direct injection technology; such as vw's tdi, and the new fsi equipped engines from volkswagen and audi, actually shut off the injectors when you are applying zero throttle, and are just coasting. The engine shuts off the injectors, which then the engine relies on the momentum of the car to keep it spinning. When it goes below a certain rpm, it turns the injectors back on, and continues to keep itself running. When the injectors are off, no fuel is used.
Today's vehicles are equipped with a EVAP system. that evaporating gasoline that comes from your tank is collected inside a charcoal canister, which is then sucked clean by the engine's vaccum system every time you run it.
The evaporating statement may have been true 50 or so years ago when gas tanks were vented into the atmosphere. But current clean air regulations do not allow gasoline to be vented into the atmosphere.
I don't know about that, all I know is that CNN claimed that 147 Million Gallons are lost this way (seemed a bit high to me too, but then again, compared to the daily consumption its not that much).
Also I have never heard of such a thing as the charcoal canister (whats the charcoal for?). Maybe you could elaborate on this a little more, as I am very interested.
This is 99% true. The newest engines that have direct injection technology; such as vw's tdi, and the new fsi equipped engines from volkswagen and audi, actually shut off the injectors when you are applying zero throttle, and are just coasting. The engine shuts off the injectors, which then the engine relies on the momentum of the car to keep it spinning.
Sounds logical and certainly possible. Audio and VW make increadible machines and their TDI (introduced in the late 80's) still beats many comparable hybrids in terms of fuel consumption, so I wouldn't be surprised about that. Since I (and many others) don't drive an Audi (I certainly wouldn't mind).
Many of the fuel saving tips don't make a difference on Hybrids either, but I really don't think that spending money on a new car will improve ones bottom line.
Thanks for the comments. You are apparently well educated in technical terms and I appreciate your input.
Also I have never heard of such a thing as the charcoal canister (whats the charcoal for?). Maybe you could elaborate on this a little more, as I am very interested.
You should take a look at this article, it has everything you might want to know:
http://en.wikipedia.org/wiki/Automobile_emissions_control#Evaporative_emissions_control
The media and news like to come up with ridicolous statements that stir up society, I usually never believe anything they say.
my mistake though, i often use the term charcoal canister, the technical and proper term is carbon canister.
edit: i also just re-read your post again, and the fuel cap has alot to do with the escaping vapors. But if it is defective, broken, or simply not screwed on tight enough, it will throw a check engine light, which results in a code pertaining to "general evap system leak".
The media and news like to come up with ridicolous statements that stir up society, I usually never believe anything they say.
Excellent point !
Thanks for the link, I will study it, but just to be sure: Wiki is written by people who are often not always experts, although I have found that if many people edit things, wrong statements tend to be fixed at some point. In the end it's often the opinion of a high level user that prevails in case a fight breaks out, and that is not always the correct opinion either.
I love working on Wikipedia and I donate some of my time (and soon pictures) too, so don't get me wrong when I say that I don't always trust them, but I have had a couple of (minor) arguments.
edit:
the technical and proper term is carbon canister
No worries, I think I understood what you meant.
Thanks for the link, I will study it, but just to be sure: Wiki is written by people who are often not always experts, although I have found that if many people edit things, wrong statements tend to be fixed at some point. In the end it's often the opinion of a high level user that prevails in case a fight breaks out, and that is not always the correct opinion either.
I love working on Wikipedia and I donate some of my time (and soon pictures) too, so don't get me wrong when I say that I don't always trust them, but I have had a couple of (minor) arguments.
agreed. I usually edit articles when I happen to find an error and I have some time. But the article I linked is very true, I read it over a couple times to make sure.
Although this is generally true, there are parts that could use some explaining. I havent heard of any tuning company that is approved by the manufacturer. Usually anything that messes with the fuel maps and timing will void your warranty for the engine. Not your whole warranty though, such as your suspension.
How a chip works, is it uses your fuel more efficiency, it leans out the fuel/air mixture to a point where it is still safe, but "efficiency" is improved. In general terms, it allows your engine to use the fuel more efficiently, creating more power, and better fuel efficiency. I'll begin using the term energy efficiency from here on, since fuel efficiency is pretty standardized towards "more mpg". When you are tuned with a performance chip, efficiency is increased everywhere, not just the lower end. In order to create the extra power, the engine needs to convert the fuel into as much energy as possible, without damaging itself.
So in short: A performance chip will allow your engine to use the fuel that is already available more efficiently, creating more power, and increasing fuel efficiency due to the same amount of power being created with less fuel.
the bold part is not true. Modern cars are equipped with Airflow sensors, and O2 sensors. If it detects the system runing to rich (from the lack of air),
it will reduce the amount of fuel that is injected into the mix, returning the fuel/air ratio back into spec.
What can be done to improve effiency though, is to use a high flow air filter, such as a K&N, or an ITG foam filter. What these do is allow air to flow easier into your engine, allowing it to require less work to "suck" the air into the cylinders. I reccomended the ITG over the K&N, as the foam filter does not require oil, which results in more mileage per cleaning, and is generally easier to maintain.
I edited the post about evaporation pointing down to your comments.
About Wikipedia: It sounds logical, but I am really missing some references. I don't agree with the current agressive removal of links that contain the slightest hint of advertisement. A long time ago some people added links to some of my websites that are fairly authorative on some subjects. Most are gone now entirely. I think Wikipedia is too agressive in that respect, so it's hard to verify anything (they only reference internal links, so Wikipedia often is its own source for reference (not a good approach if you ask me) ). Anyways, I found a couple of references:
http://consumerguideauto.howstuffworks.com/1997-to-2001-lexus-es-300-2.htm
http://www.freepatentsonline.com/5762692.html
(you see how I can link to a site with tons of ads and not feel bad about it because they are a authority).
Sorry, I had to rant a bit. Overall the Wikipedia project is great, just a bit too paranoid in my eyes.
I always check online where the cheapest gas is going to be- that way, if I"m doing errands- I will know where to stop if the tank starts to get low.
also- I do what you do- Air Conditioner at high speeds, open windows at low. ;)
"12. Believe it or not, but opening your windows will increase the turbulences and eventually cost you fuel. If you can, use only the ventilation system of your car. I cannot really gauge this against using the air conditioner. I believe that opening your windows at low speeds and using the air conditioner at high speeds gives you better fuel economy."
Yes I agree exactly, driving with air conditioned and your windows closed consumes less gas than driving with the windows opened.
I'm a purist so I preferr travel by bike and use unconventional energy sources.
Great post!
Enrico from Italy.
I'm sorry, but if the engine is turning, it's burning fuel. It's burning slowly during idle, but it's still burning fuel. It doesn't matter if it's gasoline or diesel. If the engine computer shuts off all the injectors while the car is moving, the engine becomes a large brake; due to the mechanical components maintaining their motion (crankshaft, pistons, camshaft, valves, etc.), the engine will continue sucking in air, which it will then try to compress. But there's nothing to burn, so the spark plugs will spark in compressed air, wasting electricity. And the fact that no energy is being created, and that it takes a lot of energy to compress air, means your car will stop pretty quickly when the injectors shut off. More quickly with a manual transmission, less so with an automatic (the torque converter allows the car to coast longer than a clutch does; fluid circulation versus direct mechanical connection)
Now, many cars today have the ability to turn off some of the injectors: Cadillac's NorthStar engine has had this ability for years, and Chrysler's 5.7L Hemi too when it came back a few years ago. Both can shut down 4 cylinders completely for efficiency, and NorthStar can run on 2 cylinders in the case of a major coolant loss. After all, once you get moving, it only takes about 20HP on average to keep the car moving, and 2 or 4 cylinders can do that just fine. Torque gets the car moving, and horsepower keeps it moving.
Diesels are amazing. An acquaintance last year bought a 1995 Mercedes 300DL, with a 3.something liter diesel, no turbo. According to one guy online, he regularly got 700 miles range on a 16 gallon tank in one of these. Those little VW 1.8L and 2.0L TDI engines are getting better mileage than your average Prius, like 30+ mpg more than Hollywood's favorite environmental messiah.
I check online as well. Also, I try to time my fill ups to when prices drop. If prices are high, I put what I need, when they go down -- I fill up.
When you buy a new car, you can always configure your options. In order to maximize the fuel efficiency, keep this in mind:
My wife got an email with a few gas saving tips. It said if you will get gas in the morning,
it will help because you actually get more gas because the gas is cooler and and is more
dense. Because the temp of your gas is a factor, try to keep at least half a tank because
that will help keep your gas in a liquid form instead loosing a lot when you take your cap
off. Also pump slowly to keep the gas from being volatile and loosing some to vapors.
Wow. Thanks to these tips I have been able to cut my gas consumption about 15-20%. Unbelievable how much difference it can make.
Thanks guys!
Wow... that is pretty amazing that you have been able to cut your gas consumption by so much!! These really are some great tips! With gas prices being over 4 dollars now I guess it is either find a way to consume less or ride a bike everywhere. :)
I just re-read the comments on this thread, and have a couple of things to note.
Dropping the tailgate on a pickup truck generally will not improve your gas mileage. In fact, it will usually reduce it. The Mythbusters proved this in episode #43. The aerodynamics on a pickup actually work better with the gate up. (Jamie was able to get 30 miles further on a tank of gas than Adam was, just by keeping the gate up!)
Engine knocking or pinging is caused by a cylinder compression ratio higher than the fuel charge needs. It can be caused by carbon deposits in the cylinders causing their physical volume to decrease, which increases the compression ratio. But it can also be caused by using fuel that is at a lower octane than recommended (which is why most performance cars require 89 octane or above; they have higher compression ratios than your average Hyundai econobox. Turbos and superchargers increase the ratio even more). Either way, ping in a gasoline engine is bad; it essentially turns the engine into a diesel, and for gasoline that's bad. Worst case: the engine blows a rod through the block. Say goodbye to your engine.
I love the Mythbusters! I was wondering how long it would take them to test these things and when someone would comment.
The Mythbusters are inspirational and fun to watch and most of the time their results make sense. Most of their findings are relevant and often the outcome is known even before they go and test stuff. But as sensible viewers we should always ask ourselves if the result makes sense or is influenced by the test conditions.
For instance, how come they used two different drivers for a comparative study? The mood of the driver (for instance anger) can have a much bigger influence. The driving habits (how people accelerate and brake) and other personal factors may dwarf any other result. It is intuitive that a standing tailgate will impose a greater wind resistance than a flat one that aligns with the wind flow. For completeness, they should also have reviewed the truck bed cover.
I encourage everyone to do their own testing and make up their own minds. Just because Jamie can squeeze more mileage out of a truck, doesn't disprove anything. At the very least Adam and Jamie should have reversed conditions and repeated the test to remove the variable of personal driving styles. I think a wind tunnel would be a much better proof. I drive my car with different mileage every time my mood changes. So if I want to disprove that I get better mileage, I might subconsciously work the gas pedal a little harder.
Good point on the engine knocking! It can also happen when you chip tune your car or modify the injection system to increase power. Basically the engine gets too hot and thus the gasoline ignites before the piston reaches optimal position. The explosion in the cylinder tries to push the piston against its current direction (down when it still needs to go up). This causes the knocking and the reduced efficiency. I didn't know hat inferior gasoline can cause pinging. I wonder why in some states the regular is 85 octane and in others its 87 octane.
Sounds like the regular in California is comparable to the premium in other states? Or maybe its just how the octane level is calculated thats different?
I would like to post something useful, but it is more fun to argue :) For the person who said that cars can't or shouldn't or don't shut off the fuel completely, ha! you are wrong! For the person who said it makes hardly any difference, you are mostly right, but for completeness...
I have a 1990 VW gasser that completely shuts off the fuel when foot is off the pedal (unless rpm is below idle of course). The 89 BMW 320i I once had did the same thing. This is true. I suspect that a lot of other cars do this too, and not just newer cars (actually it might just be those crazy germans, or maybe all europeans, who have cared a lot longer about saving gas). It only makes sense. That said, it turns out that on steeper hills it is better mileage to leave in gear, but on hills where you could coast in neutral, but would lose speed in gear with foot off the gas, in that case it would be better to coast. My opinion: strange practice to be putting a car in neutral and coasting, very minor fuel savings only in limited conditions.
In case someone reads this far, a bump for diesel cars. There is a reason over half new cars in europe are diesel. Besides getting great mileage, in and out of city, even when the engine has 300k miles, they are fun to drive with all the low rpm torque.
I think it would be really hard to argue with the fact that smaller lighter cars are more efficient than larger heavier ones.
As people have said, the really significant factors in gas mileage come from people simply thinking or having an attitude that makes them conserve energy. Driving smaller, more efficient cars, not minding if the temperature isn't quite ideal, walking or riding a bike when it is feasable, taking mass transit or car pooling, etc.
Tip for more mileage: you can help your mpg a lot on certain kinds of hills, by not worrying too much about keeping constant speed. To a certain extent, keep the accelerator pedal in a fixed position, and let the car slow down going up hills and speed up going down. Within limits, it makes good sense to get a run at hills. Cruise control is alright, but it could be improved for gas mileage if it could anticipate anticipate up-hills and down-hills, like the driver can.
About Daytime running lights: There is a lot of controversy about whether or not having DRL is any safer at all. Certainly safer to have lights on in poor visiblity conditions, but all the time?? Look into it. My opinion is that in the grand scheme of things, when most cars have lights on it conditions everyone to see the obvious lights, and maybe not see a car or something else without lights. Being observant and paying attention are skills that people have to train, and can easily be lost. If a person can't see an automobile in broad daylight, then they are blind and are probably going to cause an accident soon, because not every object has bright lights on it.
Just so my background is known up front, I'm a field engineer and vehicle maintenance marketing specialist that works exclusively with auto dealers (specific training for professional technicians and service advisors) and advanced automotive training for government agency fleet maintenance personal. I have over 40 years experience at various levels of the industry (working with vehicle manufacturering engineers, EPA, CARB, and most recently with the EU standards group), but for the most part my entire career has been dedicated to dealing with industry professionals and government bureaucrats. I only mention this because I'm shortly, within the confines of the company I work for, going to be providing a series of industry sponsored seminars on driving to save fuel (intended for the general consumer).
While working at putting together material for my seminars, I was searching the web looking for what others have done at providing free information (our seminars, though sponsored by various groups, are totally free to the general public), when I ran across this site and thought I would check it out.
My hat's off to Andre for taking the time to offer this website to assist people in reducing their fuel costs, good job!!!
I only wish to offer some additonal suggestions and to offer some corrections to what has been posted here.
Point One:
All motor fuels (Jetfuel, Gasoline, and Diesel) are shipped (in the USA) exclusively by pipeline, trucks are used only to deliver the necessary fuel from a local tank farm to the final retailer. In the US, there are currently 138,000 miles of pipeline and if you live in New York City, for example, there is a 90% chance the gasoline you buy for your car was manufacturered by a refinery in Houston, Texas and that gasoline got there by a pipeline called "The Big Inch", which was built in 1942.
Although the public believes there are only 3 types of gasoline sold, by Octane (87/88, 89, and 91/92), there are in fact 55 different gasoline blends used throughout the United States. These blend variations are due to altitude, local or state mandates, expected area temperatures, etc..
In Europe, and those countries that comply to EU standards (European Union standards) which is nearly everyone outside of the United States, the fuel standards (requirements) relate to fuel quality as well as complying with known emission requirements. These standards (in the EU compliance countries) are fuel type specific (gasoline or diesel) and I only mention this because the United States (specifically the EPA and the California Air Resources Board or CARB) do not recognize a difference between gasoline and diesel and their standards relate to emissions only and not fuel quality. The reference is that the United States is "fuel neutral" as to gasoline and diesel, which is very unfortunate for those of us living here.
In 2007, the EU Nations hit a milestone (Western Europe) as 54% of the registered vehicles are now diesel powered, while new vehicle sales are running 95% diesel and only 5% gasoline. Someone mentioned that Hybrids are not selling in Europe, like they are here, and that is true, but the reason for that is the diesel hybrids are only now coming on-line (in Europe) this year. Right now, you can buy a Ford Focus (in Europe) that is powered by a Ford built 1.6L turbo-diesel that gets 65+ mpg (the US gasoline powered Focus is rated at 28 mpg). The Toyota Prius Hybrid (US) is only rated at 41 mpg, but the soon to be released (Europe Only) Toyota Prius Diesel Hybrid is rated at 128 mpg (city) while exhibiting vastly greater performance at all speed ranges. Diesel is by far a superior fuel to gasoline, as diesel fuel has about a 30% greater energy value, per gallon, as compared to gasoline. So why hasn't the European manufacturers shipped these cars and trucks over here(?), ....well they can't, because the diesel we have available (specifically the new Ultra Low Sulfur Diesel) is so poor in quality, these superior vehicles simply won't run on it. To further give an example of how poor quality our diesel fuel is, the new USA only ULSD fuel cannot even be used (in all EU compliant countries) in a locomotive (rail) or marine tugboat, let alone in a car or truck!!!!
Tips to getting better mileage with your current vehicle:
1. Monitor your tire pressure weekly and keep it at the specified or recommended pressure and if you can, refill your tires (don't forget the spare) with at least 95% Nitrogen. Nitrogen doesn't, by itself, increase your fuel economy, but because the pure Nitrogen molecules are big (as compared to air), your tire pressure requires about a year to lose 1 lb of pressure, whereas plain old air will leak about 1 1/2 to 2 lbs of pressure a month. The less pressure your tires have, the greater the resistance to rolling, there by burning more fuel.
2.Change your engine oil often, every 3,000 to 4,000 miles with conventional oil and every 5,000 miles with your synthetic motor oils. And no matter what brand of motor oil you use, change it every 4 months if you don't drive to the previously mentioned mileage levels within that 4 month period. Forget what your owners manual says, the vehicle manufacturer is more interested in selling cars and if they can give the perception that their vehicle needs less maintenance than their competitors (meaning less cost to own), well they believe they can sell more cars or trucks that way. Remember; the vehicle manufacturer designs and builds cars and trucks, they DON'T make motor oil! Currently the motor oil blenders must meet the API (American Petroleum Institute) SL/SM standards (oil for gasoline engines) before they can sell their oil to the American consumer. One of the tests (of many) the oil blender must pass, to acheive the SL/SM rating, is called the "Sequential 4F" test (developed by the ASTM or American Society of Testing Materials). This test is performed using a real world engine on a test stand, where the oil is pre-heated (to a specific value) and run continuously for 80 hours (equivalent to 4,000 miles). The tested oil is allowed to have a viscosity increase maximum of 275% in that time period to pass. (most popular brands of motor oil reach 200% to 250% during this test)
If you increase your oil's viscosity (in otherwords get thicker) your fuel economy will drop and the thicker it gets, the more your fuel economy will drop. The more you drive, past that API standard of 4,000 miles, the worse your oil will get as will your fuel economy. Synthetic motor oils generally last longer because they have a much broader base additive package (also the primary reason synthetic motor oils normally cost more).
3.Avoid ALL of those consumer available oil additives (such as STP, Wynns, Slick50, Prolong, etc.), as these additives offer little as a benefit to your fuel economy and in some cases have proven to cause damage to your engine (such has been the case with Slick50 and Prolong, hench their both having paid huge fines to the Federal Trade Commission for false advertising and making misleading statements), other additives have also been fined (STP and Z-Max for example) by the FTC. There are some commercial/industrial level products (not available to the general public) that have proven to work reasonably well and generally are not very expensive (BG Products MOA is one of them), but finding them will be difficult though you can check with your local car dealer for help. We received some data from a major state highway patrol fleet that showed a state wide fuel mileage increase average of 0.78 mpg using the BG Products MOA versus not using it. Not much of a gain, but that savings calculates to about $75 per vehicle in fuel cost savings between oil changes for a product that cost about $10 on top of the cost of the oil change.
4.Fuel brand is extremely important! Buy your fuel only at the "Top Tier" rated retailers (Chevron, RDS, Unocal, and Texaco) (sorry, RDS is Royal Dutch Shell or just Shell).
Regardless of what has been posted here, I have been involved with several precisely controlled tests where discount fuels (specifically ARCO, Costco, USA Brand, among a half dozen others) were compared to the 4 "Top Tier" brand fuels and the difference in savings is astonishing. The reason for this is not because of the additional fuel cleaning additives, it is because the discount fuels are less expensive (per gallon) than the Top Tier fuels because of their higher ethanol content (generally 9.5% to 10.5% for the discount fuels and only 8% to 9% with the Top Tier fuels) allowing the discount fuels to have a lower pump price due to a greater tax incentive for using a higher percentage of ethanol.
Ethanol is an extremely poor motor fuel, primarily due to its 47% lower BTU rating over gasoline by volume. For example, many individuals have found that their new E85 vehicle cost nearly twice as much to operate as the pure gasoline version of the same model and when these proud owners of these ethanol powered vehicles find that it requires between 1 and 1 1/2 gallons of crude oil to produce a gallon of ethanol, well they are even further disappointed.
We found in our tests, that ARCO 87 (for example) reduced the fuel economy (of a specific vehicle used during these tests) by as much as 17.87% over using Chevron 87 (static dyno computer controlled test). In another test example, a specific vehicle (a 2004 Ford Econoline 350 van) was driven over a 635 mile real world highway route (that included some in-city mileage) using Chevron 87 and on the run, precisely 42.3 gallons was used at a total cost of $167.93 (pump price for the Chevron 87 was $3.97 per gallon). The remaining Chevron fuel was drained and removed from all fuel lines, then that same vehicle was filled with ARCO 87 (@ a pump price of $3.79 per gallon). The vehicle was then driven over the same test route of 635 miles and it was found that the vehicle now used 51.8 gallons @ an actual cost of $196.32.
Believe me, stay away from discount fuels, they're no bargain!
5.Transmissions:
If you have a choice, always go for the automatic transmission, for in the long run, automatic equipped vehicles will exhibit better fuel economy than a similar vehicle equipped with a manual transmission. To be completely fair, Andre is correct, if you concentrate, you will consistantly show a very marginal increase in fuel economy with a manual, but the problem is that the modern automatic transmissions are simply not like they were just a few years ago.
The average modern automatic transmission demonstrates just what can be acheived through advanced engineering and some of the newest transmissions will simply out-think and out-shift even the experienced driver with a manual transmission, its just the nature of the technology. I should also point out that the CVT or Constant Velocity Transmission is now becoming the standard and every vehicle manufacturer is offering models that include these transmissions.
Another important point is to have your transmission fluid (automatics) replaced at least every 30,000 miles, more frequently if you operate your vehicle in the manufacturers' definition of severe operation. (if you generally operate your vehicle in any one of the following: frequent trips less than 50 miles in length, above 2,500 foot elevation, stop and go situations, up and down even moderate hills, in ambiant temperatures outside of 60º to 80º F, at speeds greater or less than 55 mph steady state, carry anymore than just the driver, pull a trailer, or have an external luggage rack attached, then your vehicle is being operated by the manufacturers definition of severe operation). Do not allow your service center to service your transmission by any means other than a full 100% fluid exchange! In otherwords a transmission flush. Servicing of a automatic transmission by the old dropping of the transmission pan and draining the fluid is simply the shortcut to damaging, maybe even destroying, a modern automatic transmission. If you allow your service center to drop the pan and drain the fluid, some manufacturers (Ford for example) will void your warranty! Changing the transmission filter is not necessary, most vehicles today don't even have filters in their automatic transmissions, and many manufacturers have never had filters (Honda and Toyota for example). Filters (or more likely screens), in automatic transmissions, have never been there to filter the fluid, like with an engine oil filter, but are there simply to capture the metal particles that exsist when the transmission is first put into service, nothing more.
About 50% of the new transmissions (probably more) require extremely high quality automatic transmission fluid types and the basic fact is that these transmissions simply do not require that you change your fluid as often, primarily because the fluid engineering requirements are so high, the fluid simply last longer. Good thing too, as most of these newer fluids are very costly. If your transmission calls for Dexron III Mercon, Mercon V, Toyota Type-IV, or similar, then changing your fluid more often will not only extend the service life of your transmission, it will also improve your fuel economy as well. On those new transmissions requiring Mercon SP, Toyota Type WS, Mopar +4, Dexron VI, Diamond 3, or any of the CVT transmission fluids, changing them more often than the manufacturer recommendations is unnecessary.
It has been pointed out that when rolling downhill, it is better to put your transmission in neutral! Wrong!!!!! ALL, let me repeat, ALL vehicles sold in America are required to be equipped with an OBD II fuel management computer system and one of the requirements of these systems is that they will shut off the fuel system, its called partial or interuption programs, while coasting, but only if the vehicle is in gear. If you put the transmission (manual or automatic) in neutral while coasting, the OBD II system detects no load and the fuel injectors operate as if the engine is just idling and maintains normal idle fuel injection schedules. If you want to save fuel, do not put the transmission in neutral while coasting, period!
6.Probably one of the most important things you can do, to increase your fuel economy, is to keep your fuel system clean and deposit free. This is best done by applying a good quality fuel system cleaner concentrate. There are a lot of these out there available at your local parts store, but frankly, many are simply a waste of money. There are a few that are in fact pretty good, and the simple hands down winner here is Chevron Techron in the 12oz bottle (about $6.95 at most dealers). You can also get Chevron Techron under different brand names, specifically "Mr Goodwrench Fuel System Cleaner", available at any GM dealer parts counter (Mr Goodwrench Fuel System Cleaner is just a re-lable of Chevron Techron). Techron is actually a blend of products that has as its active ingredient a chemical called "polyeitheramine". Polyeitheramine, when mixed with any hydrocarbon based fuel (gasoline or diesel), will turn that fuel into a scrubbing agent and will desolve the gums and varnishes, seen as fuel deposits, and found throughout the fuel system. As far as the hardened carbon deposits on the intake valve or in the combustion chamber, unlike most carbon blasters or combustion chamber de-carbon agents, Polyeitheramine only attacks the gums and varnishes that hold the carbon together (under heat or pressure, these gums and varnishes react like epoxy and glue the carbon into a very hard substance). With Polyeitheramine, hardened carbon is not blasted out, but rather is dissolved into a fine powdery dust. It is also no secret that the worlds best fuel system cleaner is BG Products 44K, which like Techron is a Polyeitheramine based cleaner, but is highly concentrated. Chevron engineers have told me (directly) that their testing showed that it required "6" 12oz bottles of their Techron to have the same cleaning effect that one 11oz can of BG 44K exhibited. Unfortunately, 44K is rather difficult to find, so I suggest you go to your local parts store or GM dealer and get a bottle of Techron concentrate and apply it about every 3rd or 4th fillup. That will keep your fuel system and engine clean and running efficiently.
As one final comment, I noticed that someone mentioned they heard that 143,000,000 gallons of gasoline is lost through evaporation! I must also note that I too heard this the other night on some local news broadcast, which is simply amazing to me!!! Hehehe, what a laugh!
The truth is that the EPA did determine that approximately 143,000,000 was lost due to evaporation from the fuel tank fill nozzle, during the year of 1973!!! That is why in 1975, all vehicle manufacturers had to begin installing fuel tank evap systems.
Since the requirement of the OBD II fuel management system (ALL gasoline cars and trucks sold in America since 2000), if your gas cap becomes lose or you do not properly re-install it after re-fueling, your vehicle's OBD II system will prompt a fault code and your SES (service engine soon) light will turn on (located on your instrument panel somewhere).
Bearracing (Nevada)
>>Engine knocking or pinging is caused by a cylinder compression ratio higher than the fuel charge needs. It can be caused by carbon deposits in the cylinders causing their physical volume to decrease, which increases the compression ratio. But it can also be caused by using fuel that is at a lower octane than recommended (which is why most performance cars require 89 octane or above; they have higher compression ratios than your average Hyundai econobox. Turbos and superchargers increase the ratio even more).<<
Not meaning to sound nit-picky, just need to correct part of what you stated. Engine knock or pinging is not caused by the cylinder compression ratio higher than the fuel charge needed nor is it caused by carbon deposits in the cylinders causing their physical volume to decrease, which increases the compression ratio. In addition, turbos and superchargers have absolutely no effect on compression either.
Compression ratio is nothing more than a calculated value determined by the change in cylinder volume between piston bottom dead center and piston top dead center. If you measure the cylinder volume while the piston is at bottom cylinder than measure the cylinder volume at top dead center, the difference is then calculated into a ratio. For example, if you measure the cylinder volume at BDC (bottom dead center) and then again at TDC (top dead center) and you find that the cylinder volume has been reduced by 1/7th, then the compression is 7 to 1, nothing you do from then on can change that.
What you meant to say was that some things you do can increase or decrease cylinder pressure (adding a turbo or supercharger, or experiencing a build up of carbon deposits for example), but these still aren't the cause of engine knock or pinging.
Engine knock or pinging is caused by the fuel burning too quickly (the higher the Octane, the slower gasoline burns). Engines that exhibit knock or pinging, this condition can be caused by using a fuel that has too low an Octane rating, as the fuel is burning too fast. On older engines (pre on-board computer control systems), this could be that the ignition timing is too far advanced and the knock or pinging can be corrected by simply retarding the timing or using fuel rated at a higher octane. Engine knock or pinging is sometimes caused by fuel pre-ignition. Pre-ignition is most often caused by carbon deposits, which stay lit (hot) and ignite the fuel prior to the spark igniting.
A common error made, especially with a modern engine, is that by simply using fuel of a higher octane will increase your power and increase fuel economy, but in fact the opposite is true. Modern engines have design parimeters and computer mapping programs that function normally only if the proper fuel octane is used (nearly 90% of all new vehicles don't just simply recommend 87 Octane, they require it and if you should feel it necessary to occasionaly treat your new car to a tank of 92 Octane, be prepared for some expensive engine repairs later).
>>Either way, ping in a gasoline engine is bad; it essentially turns the engine into a diesel, and for gasoline that's bad. Worst case: the engine blows a rod through the block. Say goodbye to your engine.<<
Here, you're absolutely right, ping in a gasoline engine is not good! And you know you're in trouble when you can change a piston wrist pin without removing the engine from your car!!! heheh!
Bearracing, Nevada
Bearracing, can you clear up the apparent confusion on whether an idling engine shuts off the fuel? I say it's impossible to completely shut off the fuel when the engine is running, whether or not it's idling (how then would the engine continue to run?), but one of the other commenters says he drove a car that does shut off the gas when idling. Specifically, he claims it was a VW. As a gas VW driver myself, I call BS on that.
What say you, Bearracing?
Great tips. I like the first one the best. Reducing weight also helps. I used to keep my golf clubs in my trunk and ever since I took them out I swear I get better gas mileage.
Taking your foot off the accelerator when going down hill and having patience really add up as well. Every penny counts.
I apparently put to much info into one post, but posted above (its in there somewhere, hehe) I mentioned that modern fuel management systems will shut down part or all fuel injectors if the vehicle is coasting in gear. This is of course not true if the vehicle is in neutral, as the fuel is needed to keep the engine operating.
Although VW was one of the first vehicle manufacturers that included this system programming, almost all new vehicles now have on-board computer programming maps that function in a similar fashion. Some even cut out cylinders while cruising unloaded or at very low loads.
By a combination of this type of technology and excessive engine torque (in a vehicle of low mass and advanced aerodynamics), astonishing fuel economy can be achieved. The new ZO6 427 ci Corvette, with 505 hp and near 200 mph top speed is a good example, as this vehicle has an EPA highway mileage rating of 28 mpg. I know for a fact that some individuals have gotten over 30 mpg with this high performance vehicle.
Some of you may remember the old General Motors 4-6-8 engines (specifically available for the Cadillac and Oldsmobile lines) which actually cutout the intake valve and shut-off the fuel injector as well. This proved to be very faulty technology as if you needed acceleration, it required a few seconds for the cylinders to respond as they restored combustion temperature. Not exactly a good prospect if you're trying to pass someone when there's on-coming traffic.
Bearracing
Lots of great tips in this article, but I do have to concur with some of the other commenters.
"Riding the slipstream" seems like something best left to NASCAR drivers. Please don't try this sort of thing on the freeway :)
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money-saving-tips
Our drivin
habit has a big impact on fuel econom, thus changing the way we drive
improves fuel economy by thirty seven percent. Braking the right way is a good thing. You can save a lot by just lifting your foot off the
accelerator when approaching a stop sign on the road. And by minimizing the
time you spend with the car stopped would increase fuel mileage a lot.
On the fuel cap, evaporation might not be a big deal, but the missing cap does make the engine's fuel management system work harder. In fact, my Ford Explorer has a specific "Gas Cap" dummy light because leaving the cap off in earlier models would trigger the "Check Engine" light.
I suspect Ford was tired of people coming into the service area just to deal with a loose or missing gas cap!
==
How to Save Money
This is really incredible,Thanks to these tips I have been able to cut my gas consumption about more than 40% lesser than earlier. Unbelievable how much difference it can make. Thanks guys!
- Johan.
all tips are vry good, but i like the most is
Shifting Automatic
5. If you have a cruise control and there isn't a whole lot of traffic,
you probably should use it (it will keep the speed constant and hence
doesn't need to accelerate).
6. Use the overdrive gears, as this will generally keep your RPM down and your wallet happy.
7. Shift into neutral when you are standing still to reduce transmission strain and cool off the transmission.
I added some more information on shifting, down in the comments below this post.
most of people can do this, & it will realy very helping for save money on fuil
Alex Briganza
Electric cars are getting commonplace day by day thanks to the fact
that they have become very efficient to run and very cheap to maintain
but just like any other vehicle, electric cars also suffer the wear and
tear of time and the electric car parts need to be replaced and
repaired. This means that people are on regular hunt for electric car
parts needed for repair and replacement work.
Thanks,
Hi All,
I’m British and am glad to see some people in the US are beginning to take fuel economy seriously, although one thing that stands out for me is how inappropriate your engine sizes are! In this post people are quoting mpg figures for large engines citing them as fuel effienct, but if you want to improve your fuel costs it starts with what car you buy. As an example I drive 64 miles every day to work and back, mostly on the M4 motorway, the rest driving in to London. My car is a Seat Arosa with a 1 litre petrol engine that produces 50BHP. The car is perfect for my needs as it’s small, light, cheap to run and only produces 134g/Km of Co2, I get 54mpg if I drive carefully or about 45mpg if do 80mph to work and back.
I Guess my point is that if you only drive short distances or just commute, buy a small car with a small engine, by comparison, I used to own a VW Passat 1.8T 20V 150BHP(petrol) that was great for long cruises, I used to get about 45mpg on long trips although if I floored it a lot and the turbo kicked in, that used to go down to about 30mpg!
I think in the US you should stop making big powerful engines and build smaller smarter engines that produce the same power! On the subject of Diesels check out the VW Polo 1.2 TDI Bluemotion !!
Cheers
George