So when I went to install my upgraded battery cables I accidently broke the temperature sensor locate on the driver side rear part of the engine. After breaking 2 sensors I finally got the 3rd one installed. I also installed a b&m tranny cooler in front of the mechanical fan. I checked the coolant level because I know I lost some during sensor install and everything looked good. I started the jeep, Checked for leaks(everything good) and went for a test drive. The temp gauge immediately started rising way above 210 went all the way to 260. I turned back around to go home turned the heater on full blast (gauge did not Change) and pulled it back inside the garage. I thought maybe there was air bubbles in the system so I took the rad cap off and tried to purge the system(no bubbles came out) I let the jeep cool came back and fired her up. The temp slowly stated rising again and same thing climeas towards 260. I know the electric fan works when I turn on the a/c. I never had any type of heating problems prior to install (jeep sat right under 210 consistently). Before I start throwing parts at it. Is there something I'm overlooking or skipped? If no luck im going to drain and flush system replace tstat water pump and either swap to dual Efans or buy a new clutch. Thanks in advance!

 

Forgot to add 96 xj inline 6 aw4 199780 miles

 

Was it working fine before you broke and replaced the sensor?

 

Yeah my entire cooling system was running prefect. I also checked all my grounds for my new cables to make sure they're all making good contact. Everything seemed good.

 

i'd buy something like this (see link) and verify that it is actually running that hot..




.

 

So I'd say it sounds like the new sensor is bad

 

Agreed. I don't see how installing a new TEMP sensor would make it overheat.
I found 2 things that will drive a a XJ or MJ owner utterly insane- air bubbles in the system & a missing or broken mechanical fan shroud.
Easiest way to get rid of the air in a Renix is to park nose down on a hill. Remove the temp sensor & let the air escape.

 

I picked up a new sensor just to test it out. It was a pain to install them. Hopefully I don't bread another sensor. I'm going to flush the entire system just in case there was air that is trapped in the block somewhere and of that doesn't work then I will replace the sensor. Do you think my Tranny cooler being in front of the mechanical fan could cause that fast of an overheating issue? I have the Tranny cooler, ac condenser, and Radiator in that order. I can feel the air being sucked inward when I rev the engine but maybe it's not enough????

 

Non-OEM sensors almost always read high. I had one that read around 50 degrees high, and when I replaced it with a MOPAR OEM sensor, low and behold it read 210. You don't mention what you put in, but my guess is that it came from a parts store. Find the OEM and install it. Mopar 5602 7012.

 

Which brand of sensor did you install?
If it was not OEM,that could be your problem. Your problem being the gauge is reading wrong.
Is your electric fan comming on @ 210*? Is it comming on at all as gauge climbs to 260*?
You need to verify no air and actual temp as others have suggested. For the air possibly in the system,just slowly remove radiator cap covered with a rag when COLD,start jeep,and squeeze top radiator hose frequently while engine is running.
How did you break 2 during install?
Last,do not drive this until you verify it is not climbing to 260*.

 

It could be the problem, the part was from autozone part # tu236.

 

It is an autozone brand. The fan did not come on at any point while gauge was rising. I had to turn my ac on to start the fan.
I did the squeeze the radiator hose to get air bubbles out while engine was running but nothing came out. The fact that the coolant fluid level didn't change and no air bubbles came out, yet I did lose coolant every time I had to replace the sensor leads me to believe that there isn't enough coolant in the system... maybe? My overflow tank is full so maybe that's compensating for the loss of fluid. Im going to flush the system and purge as much as I can. Then if the guage is still reading high I will swap the sensor with the new one I have, if the problem persist I will try to get my hands on a temperature reader to verify actual Temps.. then press from there.

 

How did you break 2 during install?


I broke the other two because the sensor sits very close to the valve cover and my deep well socket had to be somewhat forced on there to properly sit in the nut. If it wasn't on properly it would turn the plastic connector causing it to break or the socket would slip snapping the connector. The third time I had to be very very gentle and constantly keep an eye on the socket. Took me an hour and a half to install and I consider myself on be mechanically inclined

 

Don't mean to thread hijack but my efan doesn't turn on unless the AC is on either I've heard it's supposed to turn on at a certain temp but as far as I know my doesn't anyone know why that happens?

 

did you plumb the trans cooler kit correctly? Also test your sensors with am ohm meter.