i have a new custom built throttle body on my car and i can't get my idle to come down. i'm pretty sure that my problem isn't with the butterfly or anything, i think that the idle air control valve isn't closing enough. my question is, does the ecu have preset 'steps' for the IAC or should it adjust and try to bring the rpms to the set 'desired idle speed' regardless of any other conditions? i'm thinking about shaving down the mounting flange where the IAC bolts in just to move the pentle in further but before i take my chances with that, i want to see what you guys say about its operation coming from the computer. thanks.

 

Jump A->B on the ALDL. Key on for at least 30 secs., then with the key still on disconnect the IAC. Start engine, the IAC will be fully closed, and that idle is what your min idle speed is.

The code had what's called, anti-stall, if the ecm thinks the engine is going to stall, it will keep it at a high idle.

 

thanks, i'll give that a try!