Heat will not start working until the temp gage is about 2/3 way up?

LIZBUZZ82

MEMBER
2000 DODGE INTREPID
6 CYL
2WD
AUTOMATIC
138,000 MILES

Ok, my heater is acting very strange. My heat will not start working until the temp gage is about 2/3 way up, the point it usually always stayes at. But usually the heat would start coming out hot as soon as it started to warm up. Now when it does get to the 2/3 mark it comes out hot and lets out a little steam which steam up the windows then no more steam and nice and hot air. But it seems to take it about 20 mins to get to this 2/3 temp reading. Last winter it didnt take it that long to warm up. Do you think my thermostat is stuck open?

Saturday, October 17th, 2009 AT 2:04 AM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

More than likely you have a blend door issue or another issue in the heater core. However the way this works is the air is routed over the heater core and when the coolant gets hot and is passing through the heater core, it heats the air that is coming into the cabin.

So if the heater doesn't work until it gets pretty hot then I suspect we have an issue with the blend door not routing the air completely over the heater core.

Here is a guide that will help with this:

https://www.2carpros.com/articles/car-heater-not-working

https://www.2carpros.com/articles/replace-blend-door-motor

The air should be getting hotter the hotter the engine gets so if it is cold and then all of a sudden it is hot then again, that is a blend door issue.

Please see the info attached below from the manual on how to replace this. Please let us know if you have other questions.
Thanks

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