Hi folks, I bought a used 2002 pontiac montana in december when it was very cold. Windows fogged up so much I couldn’t see out the side windows at all. No smell of coolent. After spending many hours of investigation, I finally discovered the problem. In the back of the glove box there is a compartment which contains air filters. I removed the air filters and looking inside with a flashlite I saw in the very back, a little higher on the firewall, a plastic door which was shut. I gently opened it. Now fresh air gets in and NO more FOG. I hope I just saved you some time so you can spend it with your family. -Andy
amolter2002@yahoo.com.
To be more technical, the filters are the cabin air filters, which filter outside air being drawn into the cabin. The door is the blend door that shuts when the air recirculation circuit is turned on, like with MAX A/C. Removing the filters and opening the blend door would allow maximum amount of fresh air into the duct system, and reduce the interior fogging.
I just hope that forcing the blend door open did not damage the servo that should open the door when appropriate.