Got '06 Civic used with an AC smell like mildew (like an old vacuum-cleaner that's been in a closet).

Cabin Filter was horrible, so I changed it and sprayed the AC dis-infectant from NAPA into the vents and in where the filter-housing is behind glovebox. Smell is the same.

The AC place said I need a new evaporator and they would clean the housing while in there ($500) but could not guarantee it. I would think not since they didn't say anything about the heater-core and I know the air goes there also...

Anyone seen this?? Can I pump some 'cleaner' into the evap drain tube and let it soak in there awhile or will it ruin my carpet? HEllllllllppppppp!!!

This has actually made me sick and when I cough now my chest smells like the crap in the car...

 

Pull the cabin filters and maybe even the blower motor and look / reach as far as you can into the ductwork to make sure there's nothing such as a mouse nest in there. Also check that the drain tube is not obstructed.