Hi Guys,

I think I have a bad IAC? Would like to get your opinion.

Two weeks ago, the car ran fine from cold start through hot shut-down. The RPM control was ok.

Last weekend, the car cold-started but the RPM's never hit the programmed value. The idle RPM was below the cold-start set-point. This idle RPM error also existed when hot.

The idle RPM is around 750 (cold or hot) which is too low for my engine combination. Engine idle is programmed for a 900 RPM idle.

The sensors seem OK. No DTC are flagged. With the key set to run mode, I hear the IAC running.

I am thinking something mechanical has happened to the valve?

I will check the wiring from the ECM to the IAC.

Any other possibilities?

Best Regards,

Bruce

 

Hi Guys,

The Autozone lifetime IAC was bad.

An AC Delco was installed.

A photo of the old IAC is attached. It shows the internals of the valve.

Best Regards,

Briuce