Good evening i will try to help as best as i can-When you checked the microfilters were they wet at all?-Do you know when the last replacement was?When looking in the cbs data in the idrive what does the display show for time left for microfilter replacement?-Smells from the vents is a common complaint which is due to bacteria growing on the evaporator/ due to the condensation that is a normal byproduct of the a/c system, it is supposed to drain out from under the vehicle when the a/c is running.I would check that with the a/c on after a while of running there is water draining out of the bottom of the car.The drains are located just about under the front seats, it won't pour out but it should drip, if not there may be some clogging in there, causing the water to back up.If it is draining, you may want to double check for any evidence of rodents under the hood.If there is, remove the microfilters and look in with a flashlight and see if any rodent evidence is in there.If everything look ok, there is a process that we use to disinfect the ac system.It actually "fogs" the evaporator and kills any bacteria that may be in there followed up with some disinfectant sprayed on the microfilters.You may want to find someone that will do this, i know any bmw dealer has the equipment to do it as well.If you have this service done i would recommend replacing the microfilters as well at the same time- hope this helps and remember that you can reply to this answer any time after accepting it- thanks-
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