Hi i have an issue with my heat. When I drive its warm bu...

Hi i have an issue with my heat. When I drive its warm but if I stop and a light or stop sign it starts blowing cold air. In park there's no heat till I rev it up. I have replaced water pump 2x, heater core, and put a new [thermos...

Hi i have an issue with my heat. When I drive its warm but if I stop and a light or stop sign it starts blowing cold air. In park there's no heat till I rev it up. I have replaced water pump 2x, heater core, and put a new [thermostat](/topics-thermostat-jeep/) in it. Mechanic's Assistant: Have you checked to make sure the thermostat is working? What about the coolant level? The coolant level is good and its a new thermostat it pops open i know bc we've been burping it. Mechanic's Assistant: What is the make/model/year of your car? 05 jeep grand cherokee 5.7 hemi Mechanic's Assistant: Are you fixing your Grand Cherokee yourself? What have you tried so far? Yeah we have put a heater core (the other went bad), new water pump, and thermostat. Flushed coolant twice burped it several times and we have had it working properly, but it always goes back to not working. Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? No thats about it

Automotive Expert
Howdy from Tennessee, I'm Chris aka Moose. Who am I helping today? I'm glad you've come here to get help. I will do my best to get the answer you are looking for. I help many customers, so sometimes my replies are delayed, I will respond once available. I try to be online at 1-5 pm and 10 pm-5 am every day. - If you get the engine to operating temp, leave it running with the blower on high and the heat on full. - I assume the heater hoses going to the firewall are not hot like the upper radiator hose? - If you remove the radiator cap and start the engine letting it run at idle till it gets to operating temp, does that help to maintain hot coolant flow to the core?

Hi I'm Jarod from indiana. So I have my jeep idling right now blower and heater on full its at operating temp the 2 hoses going in the cabin are hot 1 seems to be a little hotter but not by alot. The heat is nowhere near the temp that I used to get.
Automotive Expert
Welcome, Jarod Can you tell me the actual temp or a guesstimate on the - Upper radiator hose\_\_\_\_\_\_ - Heater core inlet\_\_\_\_\_\_ - Heater core outlet\_\_\_\_\_\_\_\_ - Center vent output temp \_\_\_\_\_\_

I dont have a way to give a temp really I cant really keep my hands on the upper radiator hose or the other two hoses going into cabin. The air thats blowing is a little warm but not like it should be
Automotive Expert
Thanks, \*\*\*\*\* \*\*\*\*\* can not hold the hoses then they are in excess of 160, so that is good and should equate to at least 140 degrees blowing out. So this points to a faulty blend door or the blend door actuator with these results. Jarod, you will need to remove the actuator and turn the door by hand to see if you are able to get more heat. If so then you know the door and core are not the problems. It would have to be the actuator. Thank you for seeking us for help, I hope I provided what was needed. Press reply if you need to follow up. If you liked my answer please let me know so I can mark your question complete. Moose

I can adjust the temperature to cold and hot i can feel it get cold ive also taken my glove box out to see the blend door turning i couldn't see it turning , but I herd it moving and the temp changes alot.
Automotive Expert
Can you try the steps I mentioned to see if you can get more door movement and heat?

I can try that
Automotive Expert
Automotive Expert
Checking in with you. Please let me know if you liked my answer, or need more help.

I haven't got to try it yet no time. Most likely be this weekend sorry ab that
Automotive Expert
Thanks for the update.
Automotive Expert
Just responding to keep the post active.
Automotive Expert
It's been a couple of days since you replied. I am going to mark your question complete for now. Reply as needed.

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