A couple weeks ago my heater quit working. I found out it was the blend door actuator so I got that fixed. It worked for about 2 hours and then quit working again. I flushed the heater core thinking that would fix it and it did for about 15 minutes. I’m not sure why it won’t work anymore. It used to blow so hot to the point where I thought my face was going to burn off. Now it works for 5 seconds and then barely blows warm if that.

 

Are both hoses going into the heater core roughly the same temperature? If not, the core is clogged...

 

Yes both hose a roughly the same. The lower hose was colder until i ran a water hose through the heater core and then it was fine

 

Could the jeep be to cold for the thermostat to open?

 

No, the heater circuit bypass around the thermostat. If you look at a picture of the front of the head, the thermostat doesn't seal the opening in the head entirely. There's a bypass channel cast in that lines up with the cavity in the thermostat housing for the heater house outlet.

https://www.cherokeeforum.com/how-to...rmostat-399026

I'd check to see if a seal has gone bad, allowing air to escape somewhere...

 

Maybe it needs another flush?

 

The weird thing about it is when my jeep gets hot around 210-215 the heater works great but when it gets down to normal temperature which is 180-190 it doesn’t work worth a crap

 

High flow water pump?

 

Normal temp is 195 to 205.....

 

I think your heater core sound like it is still plugged up in parts you need to flush it both ways and may be add a cleaner and that soak in then flush it .

 

I went ahead and flushed it out again but both hose this time and I am happy to say it’s back to burn your face off hot. Thank you everyone for the help

 

Excellent result!! How does your coolant look? Maybe the whole system needs a flush?