Jaydi

Hey y'all, earlier this week I posted about my XJs check engine light, got that to go away with a new alternator but I'm still having problems with it. The transmission still doesn't want to shift into the two higher gears. I disconnected the TCU to see if I could shift manually. I can. So I believe my Jeep has gone into limp mode, or something else electrical. Along with that comes the idle problem I now have. It is very rough and low rpm. It will stall randomly if I let it sit for a minute or two and it is never steady. Keep in mind that I was mudding when this all came about. All help very appreciated.

Jaydi

Well. To everyone in the future who looks at this post with the same problem, it was the Throttle Positioning Sensor. I don't know if it went bad at the same time my alternator did because of the mudding, or if they just happened to time themselves together. This is why I like to stay away from mud. This fixed that rough, unsteady idle and the transmission not wanting to shift from 1st until 4k revs for about ten seconds and then not at all wanting to shift into 3rd or 4th.

Roler

Since several things could have caused your issues, just curious how you worked out it was the TPS?

Jaydi

Well honestly I would like to say it was a shot in the dark. I looked on other threads with problems kind of like this but I was never really sure. I knew it was a sensor though with the unexplainable idle. Never consistent. My automotive teacher was at a loss for what it could be so that meant I was as well. Only $80 so I thought why not try it.

Jaydi

Also not wanting to bike to work at 4am made me want to try anything.

Roler

Haha. Make sure you let your automotive teacher know you solved it yourself. After a systematic approach of the problem by means of testing and excluding all possible causes like it should be done. Of course.

BooGTS

Prettymuch any time the AW4 acts up and the fluid is clean, check/replace the TPS with a Mopar one.