I've an E36, but I've had mine run through underbody washes before with no problem. Never heard of such a thing, and I've run lots of cars through lots of carwashes. I don't like to have the BMW washed that way, but when I have to...
Hmm. I'm not sure what that could be.
Proud member of the 100,000 mile club
Proud member of the I Hate SUVs club