i put ported and polished heads and intake to match heads. As i was taken it apart i had Madz28 fully tune it. After i got it all back together i went to adjust the valves with it running. It wouldnt stay ideling. Well i hook a scanner to it and it was showing that the IAC was maxed out at idle i had not cacume leaks. I drove it about 100 miles thinking it was the computer just had to relearn but never stayed idle. Do i need to drill a hole in the TB to get more air or what do i need to do.

I have CC306
Heads and Intake
and other bolt ons

 

Stock throttle body???
If so the existing IAC bypass hole might need tweaking but I don't think it would cause this.

I have yet to see an aftermarket TB with the IAC bypass drilled so if you have an aftermarket TB then I would expect to have to drill it.

The IAC counts are also COMMANDED not necessarily what it is doing. Maybe take off the TB and clean it, pull the IAC and plug it in have someone cycle the key and see if the IAC moves atall.
I had one go bad at a low setting and the car would not idle, then I grabbed a spare and it was frozen open too far so they do go bad once in awhile, apparently not often though because I could not find one in the state and had to order one.

 

Yeah sorry i have a stock TB. And i cleaned everything when i put it on there but i might have not did good enough. And it did fine before i changed the heads and intake it had only sat for maybe a week without use but maybe it went bad i dont know.

 

Crack the blades open a little bit and see if the iac counts reduce. Sometimes you have to with a h/c setup. Its an easy enough way to tell whats going on.

 

when ever i gave it throttle it went down to where it supposed to be but once you let off it will start to idle real low then finally cut off completly.