i have a 88 bronco ,351 EFI that stalls at stops after it is warmed up. i've checked for loose vacuum found nothing, changed the IAC motor , O2 sensor, MAP sensor and still have'nt figured it out. i've also replaced the throttle body and adjusted the idle control too compensate ,it helps for a while but then goes back to stalling. anyone got any ideas??? also this one had a IAC idle block spacer that i removed that seems too allow adjustment of the IAC idle for some unknown reason? anyone know why this is?

 

I am taking my truck in to diagnose the same problem. It idles ok for a few seconds then sputters and dies. will let you know how it goes. Just dropped a new engine into it so I know that it's not anything REALLY serious hahahah. Makes life interesting but hey, it's a good excuse for NOT letting anyone borrow your bronc.

tom t

 

you should not have adjusted the idle control. you probably need a new tps.

 

exactly what did you adjust? i've never seen a IAC that was adjustable, and you not suposed to adjust the throtly stop either, if you do then the IAC is gona revert back to the proper signal wich make moving the throtle stop pointless. the only adjustment is to the TPS sensor and it has to be done with a digital volt meter. Hope this helps DW