You can't it is not adjustable, It is controlled by the computor.
You have something wrong, Vacuum leak, Dirty Idle air control valve
You need to scan engine with a engine scanner to see if something is wrong with the emission system. Is the check engine light on ?? SCAN ENGINE.
There is a number of things that could make it idle to fast.
Where is the idle speed motor located at on a 1995 chevy blazer?
The idle speed is set at the factory and is NOT adjustable.
The idle speed is computer controlled on a LT1 engine. If it is a little high, try checking for vacuum leaks.
idle speed for a 99 Tahoe
The idle air control valve on the Chevy Colorado actually controls the speed of your engine's idle. The valve is sometimes called the idle speed control valve.
A 1998 Chevy Prism's idle speed is computer controlled. You will have to take it to a garage to get it set. However, the idle speed could be altered if, say, your spark plugs are seriously worn. Changing them may restore the original idle speed.
how to turn the idle down. See if it's carburetor or efi. There is a speed adjustment for either using the idle speed screw (carb) or air bypass adjustment screw. If either has no effect, see below-
The idle speed on a 1987 Chevy Celebrity is controlled by the engine computer, there is no way provided to adjust it.
replace the ecm
Idle speed is computer controlled and is not adjustable.
Hyundai accent idle speed
No it does not.