Black99Silverado, Did you figure anything out yet?

 

did you ever find the cause of this? Mines doing the same thing now...

 

Mine has been doing this off and on for the past couple years. It just recently got a lot more often, almost all the time. Replaced the IAC and it seemed to be all better...until today when it happened again. Killed the engine, started back up and it was fine again.

This is some really annoying stuff, any ideas?

sprayed carb cleaner all of the place with no apparent vacuum leaks.

Throttle body and MAF sensor are freshly cleaned too.

????

 

As well as cleaning the MAF, I'd check all of the wires going to the throttle body (IAC, TPS) and make sure that none are brittle or broken, and that all of the terminals are making good contact. If you have access to a scan tool, view the data and see what is out of spec when the problem occurs

 

Thanks for the help, will try to get a buddy to log it when it is messing up.