Why does the vents smell in my 2002 bmw 316i?

Question

Why does the vents smell in my 2002 bmw 316i?

Answer 1

does it have aircon?

it might need new gas

or have you driven somewhere smelly? past a farm or anything?

Answer 2

Given time, the AC evaporator emits a musty smell due to the growth of microorganisms in its  humid/wet environment.

And the smell from within the car that circulates into the evaporator fins add up to the problem (or is the real problem).

There are various ways to deal with this. But simply masking the smell with a deodorant is the least effective way. I suggest that you bring it to an aircon shop that could either:

a) inject cleaner solution into the evaporator cavity (this is a foamy

compound) and then run the ac blower to clean the fins,

b) or, electronic cleaning with a special tool