Oh No

So 98 xj, 4.0/Aw4. Drove it several times today. About. 2 miles around 11 am, maybe 6 at 2:00 and about 2miles around 6. Then about 10:00 I go to take a drive. It starts and idles as usual. Let it idle about a minute or two. As I'm pulling away it cuts out a bit. Then as I stop at a light it stalls. Restarts hard. Drive about a mile and its hesitating like crazy like fuel is cutting out. Did what I had to do, it barely drove and wouldn't stay idling and I needed some input on the pedal to get it to start and stay.

Get home and pull codes. They are p0123 and p0505. First is for TPS voltage high and second is IAC malfunction. Going out in the cold dark to do some quick inspecting. Only out of ordinary today was that it was sprinkling/ drizzle for most of the day.

A while back I had issues with the TPS and I ended up pulling the horn fuse and it was fine after. Tried swapping the TPS first with no change. I don't have cruise so there shouldn't be anything else supplying voltage to the clockspring I think. ?

Curious to know if these codes often are combined or what condition besides faulty wiring would cause both. Any ideas are much appreciated.

The horn is on the clock spring too. If you have a TPS / horn issue, you need a new or good used clock spring.

Fix the known problems and see if the other symptoms clear up. If you did not install a genuine Jeep TPS, it is still suspect.

Like I said, I pulled the horn fuse to cut the voltage for it to the clock spring. Goin to head out a test the TPS and IAC. Stopped home on lunch break today it it fired up without any pedal and idled ok. Took it for a drive this evening and it still cut out some on acceleration and wanted to die when slowing to a stop. But it idles ok now. It sat in the sun all day so I'm not sure if something was wet. I do get some water leaking behind/under dash on drivers side when it rains heavy. Not sure if there's anything there that could get effed up from water related to my issue. Have had lots of heavy rainstorms without this issue before though.

Ok. So interesting chain of events the last couple days. I noticed it was cutting out when I turned the wheel sharply. Pulled the 2 fuses to the airbag and it was then running normal. Did some testing and didn't find much.

So I then Jack the front end up to get the wheels off the ground. Moved wheel back and forth and found no changes in voltages on TPS connector. Didn't have any luck backprobing so I pulled the connector and tested in the connector cavities.

Noticed I was getting 4.71 volts on the signal(middle) wire. Also checked my other 98 and its reading 4.70v. So I guess that's normal. Now it gets interesting.

I put the 2 airbag fuses back in. Wheels are still off the ground. I start the jeep and turn the wheel all the way right. As soon as I do it sputters and dies. So I turn the key off then back on. Test the center cavity of the TPS and its now reading 5.62v.

So at this point the wheels are still turned hard right as they were when it stalled. For some reason I'm getting 5.62v at the signal wire to TPS. So just to verify what happened I pulled the 2 fuses to the airbag then tested center cavity on TPS again. Now it's reading 4.71v again. WTH?

Check your ABS Circuits / Connectors at the Front Brakes.
May Be Your Problem.
Glad My '96 Doesn't have ABS & All the Inherent Problems!
UncleSarge58

I actually don't have ABS either. It's definitely something with the voltage to the airbag module. Just didn't think there was a constant outage supply at the clockspring from the circuit to the airbag. So either there is constant voltage there or my problem is elsewhere. Maybe in the steering column. Idk. It's been fine these last 2 days since j removed the 2 airbag fuses. So I'll leave it at that for now. Need to finish up my other 98 to use as a daily so I can get to fixing all the stuff on my current one.