Hello- I'm new here...just picked up my second F-Body (the first was an '84) this one is a 96 Z28 A4.

I am asking about High idle and a corrosponding SES light.

I have a constant high idle 1400 in park, 1000 in gear. The PCM has thrown the IAC high idle code twice now.

Searching says the problem could be either the IAC needs to be cleaned (free) or the IAC has failed (costs money).

I haven't been able to test the IAC with an ohmmeter yet but... if the PCM is throwing out IAC high idle codes, does this automatically mean the IAC is bad? Would I still get these codes with a dirty IAC.

Thanks...

 

I would turn the set-screw that holds the Throttle Body blades inward so it closes them allowing less air in the intake..

Cody

 

I'd start with cleaning the existing IAC. It's a delicate piece so take care in cleaning it. Good time to go ahead and clean your entire throttlebody.

 

97 RedSS-

The set screw, if I remember is on the top, driver side of the TB...I can see the threads, but there is no key, flange, or edge to grip it and turn it. Am I missing something, or do I just be careful not to mung up the threads?

Thanks.

 

OK...maybe this is the one..."accelerator stop screw"...found on shoebox's site