Jeep coolant temperature help

[Destroyer]

Pull a compression test on your cylinders. These engines are just about bulletproof, but I've seen several of them with bad head gaskets. I had just about the same problem on my 98 Jeep Cherokee Sport. Turned out to be a bad head gasket between number 2 and number 3 cylinders. Fairly easy to replace, just a PITA.

[THEFERMANATOR]

Which sender or sensor did you replace? The fan should come on at 220 degrees according to the CTS. Have you pulled the radiator and cleaned out the condenser yet? As for the guage reading high, I can tell from your cluster it is a 96 or older JEEP, so it uses a sending unit mounted in the rear drivers side of the cylinder head for the temp guage. DO NOT run an aftermarket sender in one as it WILL be wrong. Also the CTS(coolant temp sensor) will be mounted in the T-stat housing if it is a 91-96, and ONLY run an OEM here as well(can't tell you how many aftermarkets have caused me grief over the years as GM and CHYRYSLER both used the same appearing CTS but with different resistance readings, and teh afterm,arket ones get mixed up ALOT). If it is a 87-90 it will be mounted in the lower ceneter portion drivers side of the block, but they use a fan switch mounted in the radiator to turn the fan on and off. Put in a OEM t-stat back in it as a lower temp t-stat does NOT stop overheating, all it does is create OTHER problems like check engine lights, washed down cylinders, poor cabin heat, and only accomplishes making it take a little longer before it overheats. These engines LIKE to run at 200-205, which happens to be the ragged edge of overheating.

Head gaskets do fail on these, but normally once they get run hot and the head gaskets go the rings break in them from it. I've pulled the head and done head gaskets to many times now and had to pull em back down to do rings to do just a head gasket anymore. Head gaskets are pretty easy to diagnose though as when they go you either get teh white smoke and coolant smell out the tailpipe, or the reservoir bottle will overflow.

Let me know if you have any specific questions as I used to eat, sleep, and breath JEEPS before I went diesel crazy. I was even a JEEP tech at a dealer, and was dam good at em. I would pull the radiator back out though if it was mine, and CLEAN teh condenser out REALLY good. This is a HUGE problem area in the JEEPS and often overlooked. Also make sure you got a max cooling radiator. I have had problems with the brass cored units fro mADVANCE, and have had good luck with the aluminum cored ones from AZ. And put a factory sender back in the rear of the head. Your description though sure sounds like air blockage to the radiator.