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ivans A8 11-15-2007 01:10 PM

Heater is hardly working. Please help
Winter is coming and I still without the heat. It would be wrong to say that I dont have heat at all, the problem that the air flow is very weak from any deflector even when set to max temp and speed. I can hear a heater motor outside, it makes a lot of noise when rotating full speed but it almost feels like air getting blocked somewhere. I checked heater core, seemed to be clean, I checked coolant flow and it is coming in to heater core hot and going out warm or cool. There seem to be no problems with blower moter since it can operate at all speeds but the air coming out of deflectors are just not enough to warm up the car. I searched the forum quite a bit and notice that others have problems with air-mix door actuator. I dont know if this replies to my case, my airflow seems to be mixes properly, there is problem in volume of internal airflow. Any sugesstions? Thanks

SSEBONNE4EVA 11-15-2007 02:30 PM

Check behind the glove box for the air mix door opening and closing when changing from heat to cool. Sounds like a blockage or damper / door problem.

willwren 11-15-2007 02:51 PM

Sometimes the buildup in the core isn't visible.

Try this:

ivans A8 11-15-2007 03:18 PM


Originally Posted by willwren
Sometimes the buildup in the core isn't visible.

Try this:

I will try that as well, but for some reason I think somewhere under the dash there is a door controlling amount of airflow inside, I suspect the problem is somehow related becoause I DO get hot air inside, it just very weak flow. Something is restricting it.

SSEBONNE4EVA 11-16-2007 11:52 AM

There is a second door that switched the airflow from top to bottom. I think its located above the center part of the dash.

willwren 11-16-2007 12:37 PM

The AMOUNT of air is strictly controlled by the fan. The amount you get will depend on restrictions, vent selection, and your fan controller.

I really strongly suggest you try the core cleaning. If your fan is actually operating at full speed, the core clogging is typically the #1 suspect. It is the most likely thing in the system capable of RESTRICTING air flow.

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