When the odor happened to me I had moved from a dry climate to a humid one. During the filter change O(that I did at 1 year not 2), I used 2 cans of Kool-it and two cans of Klima-Cleaner. Had to do it twice as the odor returned in a few days. After using entire can contents of the Klima (the cans are larger than Kool-it) and leaving the car parked with the recirculation off the odor was gone. The fans run after the car is parked to dry the evaporator and leaving it with recirculate. off seems to do a better job.