Hi. 2015 Jeep Grand Cherokee, Ecodiesel. GDE HotTune. 70,000miles. Replaced Nox sensor @ 60k. "Coolant temp out of operating range" code.
Contacted GDE for factual info about engine temps. Learned thermostat to open at 208 degrees F. During cold weather, engine oil Temp should reach 212, in order to burn off any moisture. The ecu will activate mil if proper operating temp not reached within specific time period, or during drive cycle. GDE suggested monitoring engine oil temp to estimate coolant temp, in the case of faulty coolant temp sensor.
Ended up replacing thermostat and housing with NAPA HT208-549. That NAPA part is the identical part to the original
at 1/2 the cost of discounted pricing by mopar.
Stupid O-ring was not included. I carefully extracted the stock o-ring, cleaned, lubricated and reinstalled.
I attempted to measure the o-ring size for posterity .... but could not get a reliable reading in the micrometer, due to deformation. It would be nice if anyone could provide accurate measurements of this 15 dollar o-ring, for others about to service the thermostat and housing.
Overall, the job took about 35 min. Most likely 10 min longer cause I'm obsessive compulsive about spilling coolant. My 2000 XJ has a pinhole leak in the heater core, so i smell it all the time. TRUST ME -YOU DO NOT WANT TO TACKLE THAT JOB !
Hope this info helps others !
Contacted GDE for factual info about engine temps. Learned thermostat to open at 208 degrees F. During cold weather, engine oil Temp should reach 212, in order to burn off any moisture. The ecu will activate mil if proper operating temp not reached within specific time period, or during drive cycle. GDE suggested monitoring engine oil temp to estimate coolant temp, in the case of faulty coolant temp sensor.
Ended up replacing thermostat and housing with NAPA HT208-549. That NAPA part is the identical part to the original
at 1/2 the cost of discounted pricing by mopar.
Stupid O-ring was not included. I carefully extracted the stock o-ring, cleaned, lubricated and reinstalled.
I attempted to measure the o-ring size for posterity .... but could not get a reliable reading in the micrometer, due to deformation. It would be nice if anyone could provide accurate measurements of this 15 dollar o-ring, for others about to service the thermostat and housing.
Overall, the job took about 35 min. Most likely 10 min longer cause I'm obsessive compulsive about spilling coolant. My 2000 XJ has a pinhole leak in the heater core, so i smell it all the time. TRUST ME -YOU DO NOT WANT TO TACKLE THAT JOB !
Hope this info helps others !