So my temp gauge is normally at 1/2 way (210) all the time. Today I drove home 20 miles and it stayed a 1/4 of the way up (aprrox 150) the whole way home. What's up with that? Sign's of a failing thermostat possibly. Thank's for any thought's.

 

Possible T-stat. Could also be the gauge maybe? I know my gauge went out. I put in an after market temp gauge.

 

If you have an IR thermometer, shoot the t-stat housing and see what the actual temp is.

 

use an ir temp checker at tstat housing and verify what temp it actually is. possibly temp sending unit, its mounted in tstat housing on your 2000 xj

 

I finally got my 97 XJ running yesterday. At idle for awhile, the temp was near 210 on the gauge, but about 200 on a kitchen temp gauge. The 97 has a 195 stat...

I pulled the stat out, and let run for some time, flushing out the cooling system with alot of rain water. The temp ran 145. The temp outside yesterday was about 80 degree....

 

I was having somewhat the same issue as you with my 90 XJ. I would run about 150 degrees all the time. I finally bit the big one, went to the dealership, got a thermostat from them, and put in a Stewart Warner Water Temp Gauge. Now my engine temp runs up to 195 degrees and then I can see the thermostat open when the temp drops. On the highway the needle stays at 195 degrees. So it could be your temp gauge or thermostat. I still have to test my old thermostat and see whether the gauge or thermostat was at fault. If its running cold all the time it seems to be a thermostat issue.

 

A possible quick check would be to turn the heater on, heater performance is usually very weak or not at all at actual 150 coolant temp. If the gauge is at 150 and the heater makes u sweat, your gauge is lying to ya.

 

Yes. The first thing I did was turn the heater on full blast and it is very weak. Does that mean Thermastat?

 

Most likely.

 

Alright. I'll order one tomorrow and see what happen's in two day's. Thank's Ya'll.

 

Get it from the dealership if you can, the aftermarket ones are hit or miss in this application.

 

You could check your old stat, and the new stat, with putting them in water, and a kitchen therometer, and heat the water, and see at what temp the stats open up.....
I use a couple meat therometers often in my shop....

 

Mostly a clear miss in my experience.

 

How much are the tstat's from the dealership?

 

Retail is $23.55.