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
Super
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.

What others are asking

Got a question about one of my coils misfiring

Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly. The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings...

I have a 2006 nissan altima 2.5s......when im driving my temp will go all the way up to high but drop down to the normal area when

Typically, a coolant flow issue can cause the temperature to climb while driving. A clogged cooling system or a partially opened thermostat can cause this. A cracked head gasket is a possibility but with the age and mileage of the...

Car is still overheating - 2006 Acura TL

There is no bleed screw on the 2nd generation TLs. Bleed the cooling system with the nose of the car higher than the rear if possible let it heat up at an idle until the thermostat opens and allow all...

Replaced alternator and now there's a low sounding, high pitched noise, like a jet engine whistling.

Hi and thanks for contacting YourMechanic. This can be an easy fix. The alternator may have a problem with the fan blades inside it if you got a brand new design. If you got a design with the fan located...

P0012 and P0299. Can't get power when I accelerate and rpms goes high when the gears kick in.

Hello and thanks for contacting Your Mechanic. The code P0012 means that the camshaft timing sensor is reading the camshaft is retarded. The code P0299 means that the turbo has excessive low output. Your turbo will not spool up correctly...

My steering wheel vibrates an i have a lost of power? Seems like engine is shaking

Hey there, thank you for asking about your 2005 Cadillac SRX. This is a known issue with the Cadillac SRX and is related to the steering wheel sensor. This sensor monitors the direction the wheels are turning. When it senses...

Purge flow sensor code

Hi, it is fairly rare for this to happen with a purge flow issue. Purge flow refers to the cars EVAP system. This system collects the fuel that evaporates inside the gas tank to ensure that pretty much 100% of...

How do I view the average vehicle speed?

The average vehicle speed feature is displayed on the multi-information display, and shows you the average speed that your vehicle has been moving at since the last reset. To view the average vehicle speed, press the display button on the...

Noise in the rear brakes, is it dangerous?

Strange noises are always concerning on a vehicle, but especially so when the noise you hear is coming from your brakes. With the limited information provided, it is difficult to determine exactly what is causing the noise without hearing it....