98 durango 5.2 At first it would not idle. Replaced the IAC valve. Fixed for two weeks. Drove to the store, took this one off and got a new and replaced it in the parking lot. Idling at park 2100, drive 1100. Went back and had codes read.
po108 MAP sensor voltage hi
po123 TPS voltage hi
po113 Intake air temp voltage hi
po505 IAC motor circs
What would cause all of these sensors to read hi? I went to the local junk yard and got a complete throttle body with the map, tps, iac on it off of a wrecked 5.2 durango. Put this one on. Same problems.

 

try checking the grounds on the electrical harness, but it sounds to me like the pcm is going on you ebay sells pre-flashed, plug and play units that you can buy

 

When this happened I replaced the PCM and everything was good again. For a while.