Saving gas- turn car off at lights?

Question

I've heard from many people that one of the best ways to save gas is to turn off the car while idle at a light. I would only do this for those long lights in our town that are two minutes.

However, isn't it AWFUL for your motor to keep turning off and on? The car is a 05 Camry, and we have an Accord as well- not big cars.

Any tips?

Answer 1

I have read that with a fuel injected engine shutting the engine off at any stop over 10 seconds will save gas.

I have been doing this at long lights (1 min plus) and for trains. This is relatively infrequent, so I doubt it will reduce starter life.

Answer 2

It is only awful on the engine when it has been sitting for a while and it is cold and all the oil has drained into the pan. If it has only been sitting for a minute or two, the engine should still be well lubricated. Some hybrids like the Prius do this constantly and I haven't heard of any major problems.

Answer 3

It will not hurt the engine. What will hurt is to try to start the engine when it is running already which is possible to do when doing this procedure. I have installed  vacuum switches in the wire going the starter relay to prevent this. I've done this for the ground support equipment for an airline where the engines are shut down and started 100's of times a day. Starters wear out sooner when doing this.  

Answer 4

Its not worth it. Really. As someone else said that is considered part of Hypermiling which is a new trend people have came up with to try to save gas, and hypermiling is rather dangerous. Law Enforcement is catching onto this.

Also it is bad for your car and you really arent going to save anymore gas from it. It actually takes quite a bit of gas to start a car, thus repeatedly starting it is going to cost you in the long run.

Answer 5

not all that bad for your engine, but on the whole isn't saving you all that much....

maybe it'll save some at very long lights, but don't waste your time and concentration on this during the short lights...

Answer 6

Thas insane. Please dont do that.

Think about how many times you stop at lights while driving duirng the day. Dozens of times i bet. That will wear out your starter very fast. Also it will drain your battery down. Not to mention that starting your car actually uses up more gas than letting it idle.

They call it hypermiling, and frankly some of the things people are doing are quite dangerous. They include what you mentioned to even shutting the engine off while going downhill and more crazy stuff. Its very dangerous.  

Answer 7

The minuscule amount of fuel saved by turning off the engine at a light isn't worth the wear and tear on the engine and starter motor.