Idle surges

[Doughnut]

Hi
Not sure if you can help
2000 Chevy S-10 2.2 4 liter
On cold starts the idle surges and it often gets so low that the engine stalls.
The O2 sensors have been replaced .
Any advice would be great
Thanks Ralph

[19chevy69]

there should be an idle air control module on it some where

[pat mccarthy]

yep idle air module. have a 4.3 do the same thing

[pat mccarthy]

it will not pull any codes if it is idle air my mons did not? i fix it after the best s in town put every thing new in the truck

[Doughnut]

Thanks alot for the advice.
I will check this out
Ralph

[HemiTCoupe]

I had to clean my IAC , because they get carbon on them.
A IAC (Idle Air Control) lets air in to raise your idle. it's a controled air leak around the butterfly. Usaully it makes your motor idle high, it will only go to close, not below normal idle, unless you have the base idle set to low.

Codes are for emissons & sensers. The IAC is actuator not a senser. You can check them with a 5v battery, to hear it switch, if it switch's it's good. remove & clean the inside with carb cleaner first, then test it off the motor.

Pat

[HemiTCoupe]

I agree with a need to pull codes first, to even know where to start, it could be many things to cause a cold or warm surge, Tps will, egr- evp, Vss , ect, The stator in dist does more then just sparktimming, A knock senser will retard the spark if it feels a knock.
Need to pull codes first.
It's free at most chain auto parts stores.

Pat

[HemiTCoupe]

Everytime I need to fix something on fuel injection, I have to learn alot I didn't need at the time, just to figure out what was wrong. Alot of different things can cause the same symptoms. It only helps in the long run, it's cheaper to ask question, and fix it myself, than fork out $$$$$ for them to figure it out.

Pat