[4.0 Jeep TJ Fast Idle Goes Away After Throttle Blip]

Thanks Moses, I cleared the codes and they haven't returned yet so I'll check the TPS as soon as I find a bit warmer day.  No heat in the detached garage means no working out there on cold New England days.

[4.0 Jeep TJ Fast Idle Goes Away After Throttle Blip]

New here and tried searching but came up with nothing similar.  My 06 LJ 4.0 (155000 miles) recently developed a habit of going to a fast idle/high rev of around 1500 RPM's or so.  If I blip the throttle it settles down until you take of again and it repeats.  I installed a Genright 31.5 gallon fuel tank and replaced the fuel pump assembly at the same time because it was a whole lot easier and I didn't want to drop the new tank anytime soon.  I had a code for EVAP system small leak which I attributed to the vent hose from the tank to the filler neck as the hose that came with the tank was rather short and had no clamps.  I installed it and put some zip ties on it until I could get a new section of line and clamp, which I did a week or so later.  I also had a code for O2 sensor which I forgot to write down but it was present long before these symptoms began.  I have searched for vacuum leaks but it's possible I might have missed one.  Anyone have thoughts on this?