Hey guys, weird problem here. i have a '98 camaro, 3.8l 5-speed. about two months ago, i crunk it up and it idled to about 3200 rpm and wouldnt come back down. i replaced the spark plugs and cleaned the idle air control valve on the throttle body and the throttle body itself. it was filthy. and after that it was fine. now, i crank up yesterday morning, same issue again, out of the blue. not to mention, periodically when i press too far on the gas it will choke, even when in gear or with the clutch pressed all the way. im out of ideas, dont really wanna take it to the shop when i know there's something i can do, but just dont know what. any help is appreciated!!

 

Sounds like you have a loose vacuum line. Are you showing an SES/CES light?

 

Maybe the brake booster line? If its idling that high

 

The IAC could still be bad, they can fail electrically.
For starters, pick up a spray can of MAF sensor cleaner and clean the MAF sensor and the air intake temp sensor in the intake tube. If those are filthy like the other things were, it will throw off your air/fuel mix.

 

Are you also getting any codes? But try what Camaro 69 said, and also spray MAF or Throttle Body cleaner into the TB around the butterfly valve.

 

Thanks guys, I was able to nab a IAC from a junkyard a month ago and the problem appears to be resolved except now something much worse is happening. I'm posting another question in the forum. If you happen to run across, please feel encouraged to include your input. Thanks guys!