2001 grand am high idle 2.4

I have a 2001 grand am 2.4 with an idle of 1500-2500. The local mechanic changed the iac, map sensor, and tps and still had the high idle. I replaced the map vacum hose with no help to the problem. I do have an intermittent code po122 for tps low voltage. The check engine light is off now, i have 5 volts to the tps, and the high idle still exists. I sprayed carb cleaner around with no change in idle. Any ideas???? Thanks Brad

I'ld check your wiring at your PCM and see if the contact is corroded or damaged or something...

if not try to see if you get the same voltage on your PCM and your TP...

Your wiring could be damaged or you might have a bad contact somewhere.