I have a 92 cherokee. My coolant temp sensor that controls the gauge is up front next to the other temp sensor not in the back of the engine, even though every thing I've seen is that sensor is on the back drivers side. It's a 1 wire hook up. My issue is after running for about 5 minutes my temp gauge maxes out. The engine isn't even at operating temp. I replaced the sensor shortly after I bought the jeep in March because the other one wouldn't read any temp. The newer sensor for the threaded location but the connector is a little loose. Anyone know why all of a sudden it's maxing out like that?

 

Sure that purple wire isn't dangling around between the back of the engine and the firewall?

 

Yes. there's nothing in the back, not even a spot for one. I know this is the one because when I disconnect the plug the temp drops to 0

 

Perhaps it's bad or has a poor connection then.

 

Like I said the new sensor doesn't fit snugly with the connector, but u can't seem to find any others that have the switch in the front like that.