I am working on a TBI system added to a 350. I am having a problem when the a/c is on the idle does not increase. I know I've got 12v at the computer from the compressor. It has a chip that I did not program. I'm just wondering should the programer have done something to make the idle go up. He says no, it is a faulty computer that is preventing the idle from going up. Any help would be appreciated. Thanks.

 

IIRC the computer sends a signal to the IAC valve to tell it to open slightly when the ac is on. It's not something in the program its just something the ECM is setup to do.