Hello All,

everything On my build has been running nice but I still get a random highh IAC count can can not determine why.

1989 v2500 burb, 5.7 TBI.

The truck will idle fine @~650 RPM with 25 IAC. (I have screen shots of ALDL on my shop computer I will post tomorrow).
It will run fine all day, multiple days in a row and then out of nowhere 103 IAC and idling @ ~1400. Nothing is amiss in the flag data except it shows idle cool flag and 1st time idle flag.

I am running a 180 t-stat and the temp was at 174 at the time. If i turn the truck off and immediately restart it, it is back to 650 RPM and will run idle at 650 for the next 5-10 times i drive the truck. Then, A week later back to high idle. Once it has the high idle (103 IAC) it will not go back down until i cycle the key off.

In the bin via Tunerpro i look at idle speed vs coolant and IAC position vs coolant and neither would add much with the engine at 174 degrees.

Any ideas?

Thanks,
Chris