Adjusting idle RPM

[Schwartz1986]

I've been reading all these silly articles about fuel conservation, and one of them suggested the benefits of reducing the idle speed. I know there's that little screw on the throttle body that holds the plate open, and I'm wondering if anyone has fooled with it. Are there any dangers to running at super-low RPM? Any input is appreciated.

Toby

[NYChevoo]

I havent touched mine at all. I left it at the factory setting.

[y2dgone]

I've been reading all these silly articles about fuel conservation, and one of them suggested the benefits of reducing the idle speed. I know there's that little screw on the throttle body that holds the plate open, and I'm wondering if anyone has fooled with it. Are there any dangers to running at super-low RPM? Any input is appreciated.

Toby

Not a danger to the engine itself that I know of, but if the idle is low enough and something causes it to dip your engine will stamble/stall

[petrified.rabbit]

i dont think you could adjust it down much, the computer will compensate a little, but if you move it from factory more that 100 rpm it will stall, like dan mentioned. 4 cylinders have a higher idle speed cause there are less cylinders to fire.

another thing these articles dont take into account is the age of these "how-to''s
most economy articles are not written by mechanics, so the information is passed along from article to article. and doesnt hold true for most fuel injected cars.. i cant say for the aveo specifically, but a lot of cars have an idle circuit, where it does not matter where the throttle body is set to, it will give the same amount of gas if the linkage, or gas pedal, is all the way back.. so you might just flood your car instead of save fuel..

i also have to say idling doesn't consume much fuel, but if you let the car warm up, etc.. i would suggest getting a block warmer instead of starting it 20 minutes before you leave in the morning on a cold day..

how many mpg are you trying to get here?

[ontarian_frog]

when you're stopped, idling, regardless of engine speed, you get 0 mpg.

[petrified.rabbit]

i know that, but it still accounts into the overall mpg..

[Nemasys]

You cannot lower the idle via the little screw on the throttle body, i tried it and it made the flap close so tight i had to smash the gas pedal to make it open, it gets "stuck". Its hella annoying to drive it like that and it didnt even lower the idle by 50 rpm (in fact it didnt even lower it at all) the ecu compensates.

The only way to lower your idle is via the computer at the dealer or some1 who's got a programmer for it. All cars these days the idle is controlled by the ecu.

[Schwartz1986]

Sounds like it isn't worth messing with. Thanks for the input, y'all.

Toby

[xiaogary]

Anyone knows how to adjust higher idling (using ecu programming)?
I am running high cams in my aveo, 285 degree duration. So need to adjust idling higher, or else the idling is not smooth, very choppy.