[Scenic Driver]

Originally Posted by roflcopter

I actually went to school to fix Mercedes-Benz' and one of the things they went over was cleaning the evaporator cases when they get mildewey (you can imagine how complicated the ducting is on an S-Class with about 423 motors directing air everywhere(OK that's an exaggeration but it's a lot)). The biggest thing they told us to tell customers was to let the fan run for as long as possible (ideally 10 minutes) BEFORE you shut off the car. As in shut off the A/C before you get home, run just the fan to dry off the evaporator, so when you get home and park it's not sitting overnight all moisty. Now, I'm not sure how many customers actually DID that, 10 minutes is a long time if you're sitting in traffic in 90 degree humidity, but the alternative was to cut holes in the evaporator case and hose down the fins with this insanely caustic and dangerous cleaning fluid to kill mold and mildew.

Not sure if it is the evaporator in your situation, but may be worth trying. My winter rat is a 1998 Maxima, and when it does get driven in the summer I use this method whenever the A/C is on, no smell at all.

In my last car I started getting faint hints of the mildew smell, once I started doing this I never smelled it again.