Overheat and no heat

replace the panel control or heat control valve

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These details will help.
Thanks.

Have your thermostat checked, sound like it is not working when cold.

check coolant level sometimes low level will cause no heat

Yes the heater core is starting to leak insidet he vehicle and the other could be low freon stuck temp lincage or motorJohnny

Click the link below :----http://wikisolutions.blogspot.in/2012/02/get-free-answers.html

If your "check engine" light is turn on, I suggest scanned the PCM to know exactly what fault code is stored there. Additionally, could be some problem with the "temp sending unit".

Keep us updated.

i had something similar once, it ended up being the intake radiator hose, it has a metal coil inside, mine was broken and when you revved the motor it would **** the hose shut and overheat, but under 2000 rpm it was fine .

most likely there is a door in the dash somewhere that controls the flow of the air. the actuator that controls the door for that side might be bad

Does your temp gauge read normal? if it does then the thremostat is ok,but sadly the water pump is going bad this is typical of jeeps at an idle the heater cools off because the water pump fins are worn enough to not circulate through the heater core and when you step on the gas the increased rpm move the water fast enough to circulate through the heater,it is possible that the heater core is plugged but I doubt it as a plugged heater core would not get hot either it would be cold or just luke warm all the time.