I have a 97 Cherokee with the 4.0 and automatic transmission.
So this issue started last week after wheeling. Went to the local off road park and it was a really rainy day and when we went to head home i was having issues with it not wanting to shift. It finally would shift after i reached around 3200 rpms but would never go into OD. It also began idling around 2000 rpms or so. I replaced the only 3 month old TPS and the issue was fixed.

So now to tonight. I was out messing around trying to climb some rocks and had it in 4 low. Whenever i was done and went to leave i put it in neutral and out of 4 low. When i did the rpms jumped up to around 2000 again. I drove a little bit and put it back in neutral and it jumped up again. AFter driving the few miles home it was not idling high anymore.

I have replaced basically every sensor on it but the IAC from previous issues. Any ideas on what could be causing this?

 

Any ideas?

 

Ever cleaned the throttle body?

 

Yes I have cleaned it out twice. The only sensor not new is the IAC, could this be a symptom of it failing? Its weird because the problem was completely better after i replaced the TPS with a new one. And the high idle hasn't done it again since the other day.

 

Possibly. Have you had the codes pulled?

 

As cruiser said. Have it checked for any stored codes. Even if you don't have a cel you may still have stored codes. Do this before you start throwing parts at it.

 

Whenever this happened I had the codes ran. It pulled up a TPS code (can't remember the number) and transmission module code p0700 if I remember right. I haven't taken it back to get the codes ran again yet. It still will randomly have a high idle at times. I am not sure if its a sensor or if the throttle cable is sticking. I plan on looking into it again this weekend.