Once the jeep is warmed up if I stay moving it stays at normal heat but when I stop at a stop light for extended periods of time or park and leave the engine on, the temp goes up fairly quickly to around 3/4. The other odd thing is that when the temp is at normal range the heater blows hot air like it should, when the temp goes up the heater blows cool air.

Any suggestions, any info would be appreciated. Thanks!

 

Have you verified your fans are coming on? Is the radiator clean, not full of dirt and mud?

 

the fans are coming on. as far as I can tell the radiator is clean.

 

Verify that the thermostat is opening. Fan may be coming on which is controlled by a temperature relay but the water may not be circulating through the cooling system which would explain the cool air in the heat.

 

I had similar issues with my truck and the coolant was old and bad. I flushed it put in new coolant and that helped.

 

Fixed my buddies jk this weekend and he had same issue. Thermostat. If you dont want to buy one, you can rig the existing one to stay open for now.

 

I was just going to suggest the Thermostat as well.

 

Like everyone said, it's a thermostat.

 

cool! thanks, guys. that's what I was leaning towards but just wanted a couple more opinions.