Howdy guys and girls, i hope someone can help me. I have a 96 Cherokee Sport, automatic, Inline 6. Starting last week I've been having a rough idle in gear but perfect idle in park. When I would start it it would be fine, until i put it into gear, then stumble and most likely stall, especially at stop signs. Once it died it was very hard to get it started again, i needed to hold the peddle to the floor, and would rev up rather slowly when it did finally start. Then i would put it in gear and it would just stall again.
So i did some reading and replaced the crank position sensor. Then when i first started it up it did the same thing. I cleaned the cap and rotors checked for spark etc and still the same thing. When i started it again later it fired right up, but the check engine light was on, with a reading of po118, the engine coolant temp was high. which was really weird because the engine was cold? Then i reset it ran it around the block, seem to run fine.
While I'm under the hood, i decide to give it a bath with engine degreaser and spray hose. I went to drive it again and it seemed to be stuck in first gear???????????
Im running out of ideas. I think im going to unplug the battery, unplug the new cps and plug it back in and plug the battery back in, to see if that helps any. Anyone have any ideas to point me in the right direction?
Thanks in Advance

 

Always, always follow the codes.

With your P0118 code, I would either test or replace your coolant temp sensor. Located on the thermostat housing. Not that expensive. If this sensor is sending incorrect input signals to the computer, the computer won't know whether the outside temperature is cold or hot. And that can screw with starting of the engine. Big time. Here is a link to more information on it.

http://engine-codes.com/p0118_jeep.html

The shifting problems you have are most likely a separate issue and may have been caused by your cleaning of the engine. The "throttle position sensor" hates water and when it gets moisture in it, it can directly affect shifting characteristics of the AW4.

You can test both of these sensors if so desired. But neither sensor is particularly expensive; so you could make a stop at a Jeep dealer or order a MOPAR coolant temp sensor and throttle position sensor. Do NOT buy no-name ebay engine management sensors; they are total and complete crap. You get what you pay for with engine management sensors.

Install those two sensors and see where you're at.

 

I forgot to mention, when i first got the jeep the tps was bad, got a new one and been replacing it every few months, i got sucked into the BWD one from Advanced. Anyway last week when the issue first started, i replaced that to start eliminating ideas. So i reset the jeep, disconnecting the battery. After that it ran good, the previous symptoms seemed to disappear. But i took it fora ride, and it had a really high idle, throwing PO123 which is TPS high idle. how do i fix that one? It is a brand new BWD TPS. not the best but they work.

 

So i removed the new tps out of my jeep and took the one out of my 99 wrangler. Started it up and worked great normal idle. So i put the new one in the wrangler and it ran fine in that?!?!? The issues seem to be floating. Im starting to look at grounds and maybe the computer, Although it runs fine at the moment.