Basically my temp in my ZJ 4.0 is at max about 165-175 all the time. I find it odd that its that low and was wondering if anyone else had this problem. I know its common for them to overheat sometimes, but even in the summer its this cold. Ill take a pic of the gauge when i go out again

 

Replace the thermostat. I wish my XJ would get that warm. It's usually on the first mark after the cold line.

 

thats what i figured it probably has a 165 thermo or somewhere near that, i was gunna go with a 190 if anything.

 

Or the one in there is stuck open.

 

Or HKZJ seems to run a low temp, always consistantly low, hoses, rad, thermo, water pump, fan, etc, all fresh, still shows low, but consistant.
I take it the gauge reads low. Now my only concern will be if there is a change in the consistancy. The heater blows good heat so I believe it is hotter than the low gauge reading.

 

My '01 GC w/4.0 run cool also when i got it. Temp gauge never read anything higher than 170. Its winter here in VA Beach and the days are abnormally cold. Heater blows hot but Temp gauge always read low. My Check engine light even came on and gave me a P1281 code. Motor cold too long. So i replaced the Water pump (engine has 105k miles, heard these go out at about 120-150k) and Thermostat. I installed a 180 deg unit. Temp gauge goes up to just before mid way point on the gauge and no more CEL.

My old Thermostat was stuck in open.

 

I am not totally sure what is being asked in this thread?? The engineers who designed the jeep engines intended them to run in a certain temp range.

If temp is running low, a stuck open t-stat is a very possible culprit. Replace it with a stock 192 degree thermostat. They cost $7.99 at autozone. May as well do a collant flush while you are in there, just check to see where you can get rid of coolant, not everyone takes it.

If that doesent work your temp sending unit could be having issues. That is also less than $20 at autozone, and it will take you 2 minutes to change it.

If neither of those do it, then explore the big problems

 

yea, im leaving for vacation in about 25mins and i was going to do those exact two things when i return

 

When its temp is that low it create wear to the water pump because its constantly turning... some people pull the thermostat out all together cause there broke but that just causes most costly pump repairs later...