Hi guys,

I hope you can help me with some ideas as to what the problem is. On my way home from work today I am sitting at a stop light and feel and hear a "thunk." The RPM's (and oil pressure) drop below idle and the car stumbles like it is going to die. I put it in N to see what happens. Nothing different. Then while I am sitting in N I hear "thunk" again and the rpm's go back up. Put it in drive, still sitting at the light and it does it again. It's not the transmission (I don't think) cause it's doing the same thing no matter what gear it's in. Car is a 1998 Camaro w/70k, A4, no mods other than lid and exhaust. Haven't had any problems in the past. Any thoughts? Thanks for any help!!

 

Check out the IAC (idle air control) make sure it has a good connection, if the car keeps doing it unplug the IAC while its running and see if it changes, if it stays the same its a good chance thats the problem.

 

Not to sound stupid (ok, fine, too late for that), but where is the IAC and what does it look like?

 

Go here and scroll a little over halfway down the page, theres a pink arrow pointing to the IAC while the guy has the throttle body out http://www.installuniversity.com/ins...ar/tb_swap.htm