[Captkaos]

Originally Posted by westcasey

I need help! I have a GMC R1500 throttle body injected pickup. I have had it in the shop several times. The thing keeps stalling when you put it into gear. The mechanic drilled out the idle adjust screw and moved it around. Turned it up way too high. Now I have a guy that is trying to solve the problem instead of cover it up and we can't find what the original engine idle speed is supposed to be.

With the timing set dead on what its supposed to be the truck pings on acceleration dies when you put it in gear. The EGR valve has been replaced; there are no vacuum leaks. Knock sensor is working correctly. What else could this be?? Its been hooked up to the computer and everything passes.

Would appreciate any possible suggestions.

That ain't the way to fix it... I just went through this and documented it here, I was baffled as there was several contributing factors (370K miles and it sat in a field for 2 years): http://forum.73-87chevytrucks.com/sm...p?topic=3984.0

Things to check.
A)Fuel pressure = must be 10-13lbs.
B)Injectors firing correctly = put a timing light on any plug and shine it toward the injectors (may need a dial-back to see) they should fire when the spark fires.
C)spray pattern of the injectors.
D)pull the IAC out (engine off) and see if it is gummed up? they can be cleaned.

Since someone monkeyed with the idle, I would run the screw back to where the blades are closed but resting on the stop, not the throttle bores.