Hello thirdgen people, sorry if I’m posting in the wrong place I’m brand new here. I just put a brand new IAC valve in my base model ‘86 firebird, adjusted to under 28 mm like the service manual suggests. The car starts fine and runs for like 30 seconds, with the rpm fluctuating while the new valve adjusts. Eventually it pushes in too far and cuts off airflow though, stalling the engine. Does anybody know why it’s doing this or what I’m doing wrong? Any help is appreciated.

 

Replying to let everyone know I figured it out. This video by JRobling explains it pretty well: