My focus st1 has 22k. About a month or two ago I noticed my A/c starting to smell musky and moldy. I tried turning off ac and opening and closing fresh air duct. I sprayed the car with de-odorizer and ran a/c for about 10 min. Smell was over powered by the de-odorizer for about a week and it came back. Anyone have any ideas on what I can do to stop the moisture building up or the cause.