Idle surge

[MCBlack]

2009 DJ V6 SXT AWD 121k miles no trouble codes

I'm familiar with Chevy, Ford, Honda, and Mazda. First time looking at a Dodge. Trying to help a close friend out with his intermediate idle surge. He's taken it to the stealership several times and they can't recreate the problem and basically do not help much. I feel like it sits in the shop because they don't know what to do. I've looked at it before and couldn't get it to idle surge, but yesterday my friend was coming back from Oklahoma City and left the car running for me. It was the classic idle surge. Revved 3 or 4 hundred RPM at idle, but if I touched the gas peddle lighly then it would basically have a RPM drop to nearly kill the engine unless revved to ~3K RPM. I was checking for an IACV that might be stuck like when the typical Honda surge happens its usually that, a FIT valve, or vacuum line isn't good somewhere. I can't find the IACV and I'm kind of thinking that it doesn't have one. Theres only three sensors that I can see. The MAP, TPS, and MAF. I had a bad EGR on a Chevy once and considered looking at that.

I was told that the gas pressure was good so I'm assuming that the pump is good and the line isn't blocked.

The update for the PCM hasn't been bought because 700 dollars.

Anyone know where I could start? Maybe a bad TPS sensor? Would anyone have some numbers that I reference to check with a volt meter for the TPS. I'm kind of surprised on how little information I'm finding for this vehicle. I search TPS and get TPMS all over the place. Never a straight answer.

[bigtsr]

EGR valve sounds like next best bet as this involves vacuum

which will cause surging in idle.