Help! My BMW smells like B.O...and yes, I practice good personal hygiene.

Dear Car Talk

Dear Car Talk | Sep 01, 1997

Dear Tom and Ray:

I have a 1986 BMW 528e with 50,000 miles on it! It's a great car. I take very
good care of it and I have it professionally detailed once a year. I'm a flight
attendant and park the car at the airport for days -- sometimes weeks -- at a
time. Last summer, the car began smelling like B.O.

I had several people, including the local BMW dealer, look at it, and no one
seems to know what the problem is. It usually smells the worst when I turn on
either the AC or the heat, and one person said it could be mildew in the
ventilation system.
I'm willing to do just about anything necessary to solve the problem, as we
love the car. The BMW dealer said for $350-$400 he could remove the ventilation
system and clean it, but there's no guarantee that that would fix it.

There does not appear to be mildew under the rugs, and the car itself doesn't
smell -- just the ventilation system.

Any suggestions? -- Susan

RAY: Sure. There was an episode of "Seinfeld" in which Jerry had the same
problem. I think it was a BMW, in fact. Now, I'm trying to remember. How did he
solve it?

TOM: I think he had the car stolen.

RAY: Right. Well, let's try some other approaches first. If you've narrowed it
down to the ventilation system, the first thing I'd do is make sure the AC
evaporator is draining properly. When the air conditioner is on, it removes
moisture from the car's interior. And that moisture is supposed to condense in
the evaporator and then drain out through a tube underneath the car.

TOM: If the drain is clogged up with gunk or leaves or stuff, the water
wouldn't be able to escape, and that would create an ideal breeding ground for
stinky mold spores. The drain usually can be blown out with compressed air.
It's an easy job.

RAY: If it turns out your drain IS clogged, then you've found the source of the
problem, and you may be able to just clean out the vents with a commercially
available spray product, like Fridgie Fresh or even Lysol (unless, like some
people, you think that smells almost as bad as B.O.).

TOM: Once the drain is clear, if spraying the vents doesn't get rid of the
odor, you might resort to having the entire ventilation system taken apart and
cleaned, because there may be something other than mold spores in there (like a
dead mouse, for example, or water leaking in from another source).

RAY: But I'd start with the evaporator drain. And then go up the ladder to a
ventilation system rebuild and, if all else fails, a "mysterious
disappearance." Good luck, Susan.

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