A/C musty smell
 

Anyone have a DIY fix for musty smelling a/c?

A musty AC smell is from mold growing in your system, usually because the AC drain is clogged. Make sure your car drips water under it when stationary w/ the AC running, if not, unclog the drain tube.

To prevent it, turn off your AC a mile or two before your destination to allow the evaporator to warm up, preventing condensation.

If you already have mold, you can remove and clean all the ductwork and the evaporator (a lot of work), or you can buy one of the aftermarket spray chemicals which you spray into the ducts and this spray kills any fungus, mold or bacteria in the system, usually over several treatments.

Wurth makes one ( http://www.superiorcarcare.net/w893540.html ) and so does Wynn. They're about $20/can, but well worth it if the alternative is dismantling and cleaning the entire system.

Go to WalMart in the Auto section, find a bottle of this stuff called Ozium.

Turn on your AC and spray a couple puffs in the direction of where your passenger's feet would be if you had a passenger. Oh, hit the recirculate button first.

Repeat once in a while and the mold will die and the smell will go away.

It's also a good idea to run the system for a while every month, even in cold months.

I think Ozium is just a cover-up. Plus, if the cops get a whiff, they'll think you're doin wacky weed...

Where are these ducts that I would spray this stuff into?

The vents, especially the center ones as these are closest to the evaporator.

Where does the intake air for a/c come from?

There's a recirc/fresh air valve which draws air from the front firewall (under the side panels next to the battery).