More problems with my POS lemon 2005 GC with the 3.7L. Now, at idle if I sit long enough, the temp slowly starts to rise towards Hot. Also, there is little, if any heat coming from the heater when at idle. If I give it just a little bit of gas and put the revs just off idle, the temp starts to come down and there is heat.

I've replaced the thermostat and it still does it. What else could it be? Water pump? Could it be worn enough that it doesn't move water at idle but just off idle is enough to get coolant flowing?

Emrah

P.S. I love Jeeps, but I freaking HATE, HATE, HATE, HATE this $#%$%ing lemon.

 

id clean out the heater core if i were you.

 

How do you do that?

Emrah

 

you can even use compressed air to help clean it out.

 

i know thats a 4.0 but its the same idea.

 

check for air in the system (burp it). Then check the water pump. My chevy trk. does this when the coolant gets low. If coolant is ok, the impeller on the wp may be worn enough that it's not pushing the coolant through the system.

 

It sounds like you need a waterpump.

 

X2 what he said above.^^

 

my 02 JGC was doing the same thing, i flushed out the heater core and it fixed the problem , i had a lollipop worth of crap in the heater core. that was about 5500km ago.

 

I'd say flush the entire cooling system (if there is crap in one part, there's going to be crap in the rest of it) and replace the water pump.