I think I already know the answer to this one (and am regretting giving away a spare part...)

Recently my car started running like garbage after I start it up until it warms up. It has severe throttle swings and won't stay running unless you keep the engine at 1250 or better until it is completely warm. However, if I unplug the vacuum line that goes from the charcoal cannister to the Throttle Body, it purrs like a kitten......

I think the IAC is shot and I gave away my spare!!!! What do you think??? Now I have to break out the stinking manual in order to refresh my memory on how to test it......

 

https://www.thirdgen.org/techbb2/sho...hreadid=247172

That might help you out, I was just having the same issues. Definately sounds IAC related though.

 

It's been awhile since I cleaned the IAC now that I think about it. I'll try that first and also look for my spare. I just went through my stash of parts recently and don't remember seeing it. I gave away several parts a couple of years ago to a buddy who was thinking of going with TPI on his 68 4X4 for more low end torque.

 

It could also be a stuck open EGR valve. They can get carboned up badly, and at idle it wil run like crap, and even stall, but the IAC will do this too. Just something else to look into if the IAC doesn't fix the problem.

 

I really don't want to even think about the EGR valve!!!!!! I just changed the injectors and it's a pain in the rear with the Edelbrock runners!!!!! Besides, I have a Canadian Camaro, it has a sensor in the EGR so I would/should get a code......