What's going on?

[AllTheCoolNamesAreTaken]

I had my engine swapped a little while ago. After making a few trips back and forth to the mechanic, everything seems to be fine but one thing. When I shift gears, it seems every time I disengage the clutch, the rpms briefly go up about ½ a thousand from the original rpms, then drop down. It’s fine at high rpms, but while driving normally it makes shifting rather difficult. I went to the mechanic, he took it for a test drive, and said he sees nothing wrong. Anyone know if this is normal? If not, what can be the cause? Also, at first it seemed the gas pedal was sticking. However, if the car is standing in neutral, and I rev the engine, and let go of the gas, the rpms seem to drop down regularly. Please help. I don’t know if I should go back to the mechanic and complain, or not… Thanks in advance for any replies.

[Camaro_SLP]

What engine/trans did you swap to?

[AllTheCoolNamesAreTaken]

Nothing fancy, just plain old stock. I killed me tranny first, and rebuilding was only $500 or so cheaper than a new tranny, so I got a new one. Then a little while later, I ummmm "lost" one of my front wheels about 5 miles from my house. I drove home on three wheels, so bad that the rim was scraped half-way down. This blew my engine. hmmmm... So I swapped to basically the same one with 40-some thousand miles on it.

[Distephano]

I've seen posts about this before, actualy, my car does it every now and then also. Check your AIC sensor. There is a Good chance thats the problem.

[AllTheCoolNamesAreTaken]

Yea, I heard that might be the problem. However, I have no idea where the hell it's located? Also, any ideas how much a new one would cost? How do I check if the one I have is bad?
Thanks in advance...

[AllTheCoolNamesAreTaken]

oh come on now... no one knows?

[98Camaro3.8]

http://home.cfl.rr.com/mkaprocki/Camaro/L36_Diagram.jpg
IAC is #2.