Forwarded by a friend who read it on an M-B message board...sounds hard to believe, but....draw your own conclusions.

I was in the garage swapping out the air filter in my '00 M5 last night. The door's closed, so naturally I'm only wearing boxers and kneepads. My wife starts up the car so I can make sure there's no leaks or whistles. I'm straddling the engine like a pony so I can get real close to the filter and hear everything. I give her the thumbs up to bring up the revs. At what must have been 5000 RPM, the VANOS system kicks into high gear and triples the airflow in an instant.
My groin, which is 3 inches from the filter at the time, gets violently yanked toward the filter. My scrotum gets pulled through the dick curtain in my boxers and gets jammed in the cleaner. My wife (an epileptic) suffers a petite mal seizure and cannot take her foot off the throttle. She leaves the engine banging against the rev limiter for a solid four minutes until she faints from the exhaust fumes.

I call BMW Roadside Assistance on my cell phone. They don't believe my story and hang up on me. My wife finally wakes up. She cannot free my genitals from the air cleaner, and I am too afraid to "rip this band-aid from my wee-wee." My wife detaches the hood and we drive to the hospital. She goes slow, because I have to crouch like a baboon over the engine with my genitals and rectum rubbing against a now-overheating engine. It's an embarrassing 30 minutes, most of it on the freeway.

We get to the hospital, and I wait in the parking lot an hour while my wife gets a nurse. The nurse says she can't help. We drive to the BMW dealership and have a mechanic disassemble the airbox. He finds pubic hair jammed in the intake. Total cost: $1450, not covered under warranty.

THIS IS NOT A JOKE. If you have a VANOS-equipped engine, be VERY careful when doing your own maintenance.