I have a 2000 1500 with a 5.2 and 60,000 miles. It has been idling rough for a few weeks and today it started idling REALLY high. It'll do 50 without touching the pedal.
In the last year it has received a new crack position sensor, iac, and two ecu's (both covered by dodge under the federal 8/80) , and a fuel pump. Any thoughts on what next?

 

The IAC was replaced? That's good. BUT, was the IAC port and the IAC inlet slot under the port ever cleaned???

Check out this step-by-step method of cleaning the IAC and those nasty TB ports too here ...
https://dodgeforum.com/m_525409/tm.htm

Also, clean the electrical contacts to the IAC and the TPS.