I have a BMW 330d (E46 – 2005) About a year ago, I noticed that if I turned off the Aircon (but left the fan running), a musty, damp smell would seep through the vents, filling the car with unpleasant aroma. This meant that I either had to have the Aircon running all the time, or be too hot. After some google searching of similar problems, I bought a can of Carplan Kleen Air from eBay (£6.95...
Carplan – Kleen Air review
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