1997 k3500 hard to start/stalls

I have 1997 k3500 with the 350 in it that runs good when its sat for a day but when the car heats up it won’t start without giving it gas and when you put it in gear it sputters and wants to die unless I give it gas. it also hesitates for a split second on acceleration. this is all when its warm. only 108k on it. I was wondering if anyone has had this issue or had some insight on it

The idle air control valve may be effected by heat.

The IAC valve controls the engine idle speed under all conditions.

The hesitation may be caused because the iAC valve isn’t going to the proper position when the throttle plate opens, allowing too much air into the engine for a slit second.


hi i ended up finding what it was hooked the scan tool up and when I viewed data the temp sensor was reading at -40 and the engine was never getting out of open loop which was flooding the engine when it warmed up

That’ll do it!

And no Check Engine light?


there were codes but no light pending codes