It seems my jeep is running a little hot..above 210..usaully happens when the air is on or going up a grade.. Had coolantr changed didn't seem to help

that is on the high end of normal, the thermostat is probably a 195 that is fully open at 210-so it really should run around 210 in warmer weather, and cooler if the air is cooler. check the coolant level, make sure the fan clutch 'slips' when you turn it-it should only spin about 1/2 a turn when you spin it by hand, if it is loose, it is not working properly, and if it spins too hard it is going to use a lot of gas and will be hard on the water pump bearing (and be loud). If you have doubts about the cooling system, change the thermostat to a 180, flush and full the radiator with new antifreeze (50/50 mix water and antifreeeze). Make sure the front of the radiator is clean so air can go through the fins, and check the upper radiator hose when the engine is hot to see if the hose is hot and has pressure (can't calopse the hose due to pressure buildup)-if you cannot, check your radiator cap, it might be defective.

If you have the 4.0L six cylinder those run hot. 210-220 degrees. If the cooling system is fine, both fans are working and it's not overheating you can try adding a bottle of "Water Wetter" to the coolant. I also changed my radiator cap to an 18psi which seemed to help run slightly cooler. You find it at the autoparts store.

The temp reading on the dash is a very big clue... Likely the thermostat (at the end of the large top radiator hose inside the metal housing) is stuck open. When that happens, the coolant in the engine never reaches full temp. Not only can that result in a low heat condition but it can also give you poor fuel mileage as the computer always thinks the engine is cold and therefore it adds extra fuel to keep it running.
Replace with a 195 degree(f) thermostat, run the engine (with the heater on full heat) to nearly normal temp, turn it off and wait about three minutes, then re-start and continue filling. Once full, add whatever is necessary to the recovery bottle and close it up and check for leaks.

you could have bought a bad thermostat,it happens.the clutch on your fan could be going bad also.that would be my suggestion[bad clutch on fan] if @ when it gets hot again, shut it off and then try to spin fan by hand, if it spins easily, it's bad.in other words, the clutch on the fan is designed to kick in and spin like crazy when the engine heats up, you should even hear the difference in the sound of the motor.a whirring sound. i hope this helps you out!!!

thermostat?

replace the thermostat just to be safe. not to do so is what i call to gag on a nat and swallow a hog. then pressure check the cooling system to make sure it is not making pressure above what is on the radiator cap. if it is you may have a blown head gasket. make sure yer not gettin antifreeze in the oil.

Since you added coolant, now it is time to check the fans. If the fans do come on, than your thermostat needs to be replaced, Should be done every 4 years anyways.

1st 210 is on the really high side, get a lower temp thermostat say 160 degree for it, the reason it dies and wont start is the computer tells its too hot to run safely thereby kills iginition to save you a ton of cash, also check your cooland if its got a lot of rust or is a nice rust color i mean completly brown have the motor reverse flushed and ahve htem look for particles if possible,,,,
my 95 had the same issue i ended up changing out the water pump , radiator and thermostat

Sounds like a CPU problem. your radiator may need a good flushing a s well. i would also check the heater core for any unusual problems like seal break or leakage.

um...strange ...engine temp reaches 210 before thermostat opens and lets water circulate ..fans go on before that normally..180 or so..hot air from heater going to cold air? strange...could you elaborate for me /us?