[Podborodok]

1. Do you save more gas when you have your car at neutral gear instead of D at red light?

2. Do you save more gas if you use vent instead of air conditioning? How about heater?

3. Is using gear break (shifting down) better than using too much breaks when slowing down/stopping? For example, is switching to D -> D3 -> D2, etc to slow down better than just using breaks?

4. Does turning on heated seats use up gas? Bad fuel economy?

5. Is it a good idea to "warm up" the car before you start driving? For example, waiting about 30 seconds to 1 minute before you start driving after ignition.

6. Is it better to change your engine oil more than you are required to? For example, changing your engine oil every 3000 miles instead of 5000 miles like you are required to.

7. Is it a good idea to put premium fuel once in a while to "clean" your engine even though your car requires regular unleaded?

8. In the United States, are ARCO fuel really bad compared to Shell, 76, Exxon, etc?

9. How important is it to get those "recommended" 10,000, 30,000, 50,000, and 100,000 mile services for $100-200?

[jakitula]

A basic rule of thumb is: do exactly what's written. Basically a team of engineers tested cars and gave precise figures which are best for the car.

1) Yes in older cars. Modern cars know when you are on a red light and disconnect the gearbox. As soon as you lift your foot of the break... it snaps the gear in and you are off. You can feel this when you are on a red light and suddenly the motor sounds more relaxed.

2) Efficent air cooling on a car qould require big fans, big fans use a lot of power. The combination of a radiator and a water coled system is by far more economical. On a buggy though it is easier to use an air cooled system as that vehicle needs to be light and robust.

3) Shifting down is great on a manual (for lots of reasons, too lazy to tupe them all out). Not on a automatic.

4) Yes, as you need to create heat. The heat is created by electrical wires in the seats. The motor generates electricity. But you don't use heated seats all the time, and when you use them the fuel consumption is negligible.

5) Big YES

6) No need for that, just don't go over the 5000 miles

7) Use exactly the fuel that your car is made for... everything else can cause problems.

8) I'm not in the US

9) Very important, I'd say crucial. If you want your car to purr like a kitten [thumbup]

[Giselle]

1. Do you save more gas when you have your car at neutral gear instead of D at red light?

Yes, but not as much as turning it off - many modern cars will do this for you, restarting when the brake is released.

2. Do you save more gas if you use vent instead of air conditioning? How about heater?

"Vent", or open window? Using the fresh air vents should be negligible either way, windows are better up to approximately 80-100kph (50-60mph), depending on vehicle - the increased wind resistance will generally make A/C more economical after that.

3. Is using gear break (shifting down) better than using too much breaks when slowing down/stopping? For example, is switching to D -> D3 -> D2, etc to slow down better than just using breaks?

IMO, using anticipation and coasting to a stop, using the brakes if required, is the better policy, overall. Modern vehicles may shut off the fuel on coasting/over-run but the attendant engine and transmission wear, IMO, is greater than the wear to the brake pads and rotors, certainly of greater expense.

4. Does turning on heated seats use up gas? Bad fuel economy?

They require electrical energy which is produced by the engine, I would expect this to be barely noticable, though.

5. Is it a good idea to "warm up" the car before you start driving? For example, waiting about 30 seconds to 1 minute before you start driving after ignition.

Generally, a BAD idea - it is when the engine is using the highest fuel/air mixture with the attendant high dilution of the lubricating film on the bore - increased wear. It is also using the fuel without moving the vehicle.
However, in extreme conditions, a short idle period may be a good idea to ensure oil flow.
In either case, IMO, little more time than required to put on your seatbelt after starting the vehicle.

6. Is it better to change your engine oil more than you are required to? For example, changing your engine oil every 3000 miles instead of 5000 miles like you are required to.

Depends on the operating conditions, manufacturers recommendations, oil type used, whether the filter is also changed, etc.
If the vehicle is used for short runs, in traffic with extended idle periods, in the low gears, in winter when it doesn't warm up, then changing the oil more frequently is a good idea as it would suffer from oil dilution from the fuel and condensation of water in the oil. If the vehicle is used in warm conditions, used mostly for long trips, is primarily used in the high ears, is rarely used cold, then the oil change period can be extended.

7. Is it a good idea to put premium fuel once in a while to "clean" your engine even though your car requires regular unleaded?

Using a higher than specified fuel grade is generally just a waste of money - however, some people have actually experienced better fuel economy and/or better running from a higher grade fuel - esp' if the engine has an engine management system that will advance the timing to benefit from the higher octane. It's your call if the additional fuel cost will pay off.

8. In the United States, are ARCO fuel really bad compared to Shell, 76, Exxon, etc?

Don't know, not in the US, however, most companies get their base fuel from a common distribution network and add their own additive packages.

9. How important is it to get those "recommended" 10,000, 30,000, 50,000, and 100,000 mile services for $100-200?

It is a very good idea to use the manufacturers recommendations - they should know what is required - esp' when it comes to sell the vehicle as it looks like the vehicle has been well looked after. Esp' in Europe, people like to see the stamps in the service book.

Just IMO, of course.

[LindaSmithIV]

Just IMO, of course.

I have never been able to convince any of my co-workers that leaving the car to idle for 5 minutes to warm up is not a good idea. They just cannot understand when I explain to them that it's better to get going after only a few seconds but keeping the engine load low. I try to explain to them clearence tolerances and such but all they've ever heard is "warm your car up before driving".

You don't happen to have a link to a reputable publication that they can read and I can finally get them to stop thinking I'm an idiot [rofl]

[envenonearo]

I have never been able to convince any of my co-workers that leaving the car to idle for 5 minutes to warm up is not a good idea. They just cannot understand when I explain to them that it's better to get going after only a few seconds but keeping the engine load low. I try to explain to them clearence tolerances and such but all they've ever heard is "warm your car up before driving".

You don't happen to have a link to a reputable publication that they can read and I can finally get them to stop thinking I'm an idiot [rofl]

I've had that same discussion with co-workers a hundred times. No one seems to listen.

[envenonearo]

I have never been able to convince any of my co-workers that leaving the car to idle for 5 minutes to warm up is not a good idea. They just cannot understand when I explain to them that it's better to get going after only a few seconds but keeping the engine load low. I try to explain to them clearence tolerances and such but all they've ever heard is "warm your car up before driving".

You don't happen to have a link to a reputable publication that they can read and I can finally get them to stop thinking I'm an idiot [rofl]

Is Popular Mechanics reputable enough?

http://www.popularmechanics.com/auto...o/4213313.html

[EntectCelpelm]

Air con uses more fuel, cool the car with the windows open for a few minutes before turning it on. If your car has been sitting in the sun it will take a lot of energy to cool it down to a chilly temp.

Going down through the gears on an auto is a joke really, going down through the gears with a 'stick' is still a joke. It is purely a waste of fuel. You have breaks for stopping the car, use em.
If you are on a race track that's a different kettle of fish though.[thumbup]

Warming up the car before starting off causes a lot of conjecture. I think it's been proven that most ware on an engine occurs when it's cold BUT to sit there warming it up in stead of driving really easy for the first couple of minutes is a waste of fuel.

Regular servicing keeps the value of your motor higher, buyers love a service history. It can easily add quite a few hundred £/$ to it's resale value.

[Giselle]

Re: "warming up the car". Most car owners marnuals actually mention it's best to drive after starting rather than leaving it idling. Besides, it warms the car up much faster which means less fuel erichment, anyway, so that's good as well.

I forgot to comment on the heater use - this uses waste heat from the engine coolant so doesn't affect the fuel economy - if the heater wasn't being used it would be ejected by the radiator. Using the fan will use a small amount of energy but I would expect this to be negligible.

[lollypop]

So it's not good to leave the car to warm up?

EDIT: Just read the link, it says for newer engines. Any timeline for these newer engines? How about the engine for a Volvo 240GL and 740GL Injection?

[Giselle]

So it's not good to leave the car to warm up?

EDIT: Just read the link, it says for newer engines. Any timeline for these newer engines? How about the engine for a Volvo 240GL and 740GL Injection?

I would guess he meant anything built in the twentieth century !

[jakitula]

The guy actually said: is it ok to let the engine run for 30 secs or a minute before driving off.

Not 30 minutes ... 30 secs to 1m is just right... you get in the car, start the engine ... look around for traffic) and drive off.

[Podborodok]

Thanks so much for the answers guys. Lots of good information.

I still have few questions left though. I'm still not sure if having your car in "neutral" instead of "D" gear saves you gas or not. Sometimes I get stuck in red light for a while and when I change the gear to "neutral," I can tell the engine sounds different. However, I'm just not sure if that actually saves gas. I heard turning off your engine completely during red light saves you more gas but I think it uses more gas to actually restart the car.

I drive a 2007 Honda Accord and I'm not even getting close to the advertised MPG whereas I was getting more than the advertised MPG with my 2004 Hyundai Elentra and I have not changed my driving habit. I drive exactly as I did before. I try not to accelerate too fast and don't even break too often. I'm just a little confused here.

[Pvfcadbh]

how much milage is on it cause you wont get full mpg till its broken in, btw if your at a light and shift it into nuetral and your rpms are the same your using the same amount of gas

[gardenerextraordinaire]

Thanks so much for the answers guys. Lots of good information.

I still have few questions left though. I'm still not sure if having your car in "neutral" instead of "D" gear saves you gas or not. Sometimes I get stuck in red light for a while and when I change the gear to "neutral," I can tell the engine sounds different. However, I'm just not sure if that actually saves gas. I heard turning off your engine completely during red light saves you more gas but I think it uses more gas to actually restart the car.

I drive a 2007 Honda Accord and I'm not even getting close to the advertised MPG whereas I was getting more than the advertised MPG with my 2004 Hyundai Elentra and I have not changed my driving habit. I drive exactly as I did before. I try not to accelerate too fast and don't even break too often. I'm just a little confused here.

With a car that new an fuel efficient, you will not get anything out of shifting to Neutral at a stop light. You will save by turning the car off, though. It hardly takes any fuel for a new car to start up and the amount saved is pretty nice if you are at a long light. I have a 99 civic and I get 32-35 MPG on city driving. The biggest thing I do is I never go above 60 MPH because it is not fuel efficient after a certain point. Find the sweet spot on your car. For my civic I get the best efficiency around 55mph.

Also you might want to put some fuel injector cleaner into the gas tank next time you fill up.

Take a look at where you car is idling at, IE how many RPM's does it idle at? The RPM's at the stop light should be roughly equatable to the RPM's when the car is in neutral and at idle. IE - My civic idles around 1,000 RPM in neutral and probably at about 800-900RPM when in D4 and just sitting there.

We bought a 2004 accord v6 and the dealer recommended that when we weren't driving on the freeway to put the car in D4 instead of D5. Not sure how much gas that saves or whether it saves any at all but if you have the bigger v6 you might want to try it.

Try checking your tire pressure and wheel alignment too, low tire pressure or misaligned tires are very bad for gas mileage.

As far as gas goes, check this thread, http://www.futuremark.com/forum/show...&highlight=gas

And, a nice government resource
http://www.fueleconomy.gov/feg/drive.shtml

If you want some more resources for your Accord, I like this forum...http://www.honda-acura.net/forums/index.php

If you can't tell, I am damn proud of my Civic and it's gas mileage

[Deseassaugs]

What kind of mpg are you getting? You really want to be easy when accelerating off a light to get the best economy and you want to make sure tire pressures are at the recommended levels and that you’re not carrying any extra weight (random crap in your truck, etc). Even with all that, those estimates are under controlled laboratory conditions with windows up, any extra stuff turned off, and at a cruising speed of like 55mph (for the highway rating) so they’re not really real world conditions. Buy a couple car magazines that include reviews and road tests of your model car or check to see if you can find reviews online and see what their observed average economy was; it’s probably going to be much closer to real world conditions and what you’ll be experiencing.


From my understanding I think the EPA is going to change its testing methods for mileage estimates but I’m not sure when that will actually start going into effect.

I would say if you’re getting within 10% of the rated numbers you’re doing great and when you just don’t really pay attention to your driving style maybe even within 15% or so.


For a new car like that, read the service manual and follow its recommendations. They outline the best car for your car and there really isn’t any reason to find hidden “tricks or tips” to take better care of it, it’s not a big secret.

[Deseassaugs]

how much milage is on it cause you wont get full mpg till its broken in, btw if your at a light and shift it into nuetral and your rpms are the same your using the same amount of gas

I thought there was a huge debate awhile back that went on to MANY replies and it was finally decided by the masses that modern engines don’t need a break in period.

[Podborodok]

I have a 2007 Honda Accord EX-L automatic. EPA estimate is 20(city)/29(highway) MPG. I don't accelerate too fast. I try not to speed up too fast and rarely use A/C. The car only has 1100 miles on it since it's brand new and I've been trying to get the best MPG possible but I only get about 18(city)/25(highway). I have nothing in my trunk and I drive alone.

I'm a little concerned because I was getting 24/36 MPG with my 2004 Hyundai Elentra. The EPA estimate on the Elentra is actually 24/32 MPG. I was actually getting alot better MPG than what was advertised. I know Accord is a bigger and stronger car but I'm just worried because I'm even coming close to the advertised MPG.

When I shift down to "Neutral" from "D," I can already hear the engine quieting down. It sounds more relaxed. Also, I don't have to hold on to the breaks to prevent the car from moving when I have it in "Neutral" at a red light. Am I actually saving gas or wasting it by doing this?

Anyways, any additional help will be greatly appreciated. Thanks so much!

[Evoncalabbalo]

What happens if your car has an auto gearbox, but has a manual sports shift?

I constantly use it because my last car was a manual and I feel way more in control of the car if know exactly what gear it's in. I shift down as I slow down... mind you the car will shift down on its own but at a lower car speed. In fact I've found it way more fuel efficient to drive it with the sports shift as at 60km/h the car doesn't go in its top gear (in normal auto mode). The engine and gearbox feel fine cruising at that speed at a nice 1200 RPM.

The only (small) concern I have is the down shifting if I might wear the gearbox out. But something tells me if they put the sports shift in the car the engineers probably would have given it a good thrashing to make sure the gearbox can take it. Though it is a medium size family car at the end of the day and most people would drive it in auto.

Despite what you guys might say about it on FM the fact is I'll keep doing it because I feel in control and I know exactly what the car will do and how I can react in a situation.