I have a 2012 Rubicon. I have been getting a P0198 trouble code, which makes the jeep lose significant power. I have replaced the oil cooler, both oil sensors, as well as the thermostat (it previously had a P0128 code). Does anyone have any experience with this issue and can relate what the potential source of the issue is / fixes? Any feedback on this would be helpful. Thanks.

 

Wow you are throwing parts at it. Oil over temp is the code. If you can clear the code then start it cold and note the temperature when the CEL comes on. That's a good start. Could even be a shorted signal wire from the oil temp sensor. That requires a visual check which just costs time as the harness may be worn through which is common in older Jeeps. The power reduction is simply the ECU saying it wants to save the motor by reducing power which keeps temps down a bit.
Just as a "I always do this" thing. Every time I am under the Jeep on a creeper I inspect the wiring from one end of the Jeep to the other to look for broken ties, frayed or wiring that may be chafing, fuel lines, cooler lines, brake lines etc. Last time my inspection caught the flexible engine oil cooler line (Chevy not Pentastar) rubbing on one of the engine pulleys. Work one should do to keep the vehicle reliable.

 

i have the same issue with my 2017 jku. I’m getting the P0198/ P1239. Ty2_QbXs
I’ve changed the oil housing to the Dorman 926-876 upgrade aluminum oil housing I change both sensors on the oil housing I changed the wire harness and both knock sensors
upper & lower intake gaskets, as well as the thermostat. Did a coolant flush and added new mopar concentrated coolant and cut it with distilled water, did the oil change and filter I used pennzoil Platinum sae 5W-20. I also changed my spark plugs to NGK Laser Iridium. This issue started from the dealer from over torquing the oil cap and cracking the oil housing. The dealer replaced the oil housing but soak my knock sensors which are directly under the oil housing and saturating the wire harness and connectors. So now the code P0198 keeps coming back to haunt me. I’ve noticed when my Jeep is on/running but stationary not moving the code P0198 (check engine light) would come on. Not all the time but it has came on since I’ve added all the new added parts. I haven’t been getting the P01239 code just the P0198. It’s driving me nuts and I can’t figure out what the issue is. If anyone knows the solution please reply to this thread.

 

Update: I had the cooling system flushed @ the dealer. Code disappeared and hasn't returned in over 6 mos.
Thanks for the additional insight folks! Hope all works our for you.

 

I did a PCM flash and that solved my issue thanks you the update✊🏼

 

[QUOTE=Lucille;4389648]I did a PCM flash and that solved my issue thanks you the update✊🏼[/QUOTE

Did you have to do that at the dealer?

 

did you have to take it to a dealer to flash the pcm or is it possible to do it yourself?

 

i know a guy that works at the dealer that comes to a shop where I get my Jeep serviced at. But the flash didn’t fix my issue I still have a check engine light P0198, the flash just hid the code for a few months. I can’t figure this issue out, I recently changed the oil pump,water pump and I’ll be changing the transfer case because I have a knocking noise coming from the transfer case. I can’t stand Jeep Wranglers anymore to many unexpected unnecessary issues with these vehicles. They are cheaply made. I purchased this Jeep new and out of all vehicles I’ve owed Jeep is the worst they are definitely a Money pit. I’ve yet to take my Jeep off road I’m afraid something else will happen. I just can’t get rid of this P0198 code I also changed the oil temp sensor twice and wire harness. Very stressful.




JL Style grill on Jk

Fast back hardtop with slanted tire carrier, hardtop with dual power sunroof. JL tail lights.

JL style Front Fenders, 35” tires 2 1/2” lift, power steps