I'll turn up the temp on the dual control to get heat, and/or the defroster to blow warmer air. All I get is cool air that makes for an uncomfortable ride and slower defrost. I did replace the blower motor in the summer, could this have caused the problem by not hooking something up correctly?
Only the cold/cool air comes out of my unit. I have checked the control panel (removed and opened) to ensure the device was moving properly from side to side (cold to hot), it does. I then checked the battery, making sure the reset, from having my mass air flow sensor replaced didn't cause a misread to the electrical system. Today, I find it is the accualtor door. Part $91.06 plus tax, Nash Cheverolt, and $117.00 for labor. I did it myself, it was approximately 10 screws and 30 mins (or so) of laying uncomfortabley on my back.- no jokes, please. Heat works like a champ and the Buick gets to live another day in my garage.
Had the same problem. Mechanic flushed out the entire engine and cleaned out the gunk that had built up. Now I have heat after nearly 2 winters without it. Be sure to have them check all hoses and connectors after the flush out; I had a leak within 5 days from 2 elbow parts (plastic) that disintegrated because they had pretty much been held together by the gunk inside.