Has anyone heard something like this?

My 08 535i has < 2000 miles on it and for the last week or two it makes an odd grinding noise when I turn teh car off - maybe 7 out of 10 times. It sounds like a fan or something is rubbing against a plastic cover or manifold. The noise lowers in speed/pitch over about 3 seconds and it's loud enough that people look at the car.

Here's the best part! I took the car today to a BMW service center and the mechanic said it was normal! He said it's the waste gate. I started laughing on the phone and I think I pissed off the Service advisor. I've owned turbo cars before - I know what a waste gate sounds like and it makes no sound when the car is idle, yet alone being turned off.

Any ideas / thoughts? Maybe I need to take it elsewhere - what a joke.

 

Not that there's any particular relationship to your situation, the exact same situation developed for me with the Ford dealer a few years ago about my turbo diesel pick-up, the grinding noise that initially I could only barely detect as a very high frequency ticking on shut down and spin down. The shop told me it was "normal" as well. It got worse over a couple weeks. Took it in three times, during which I had been reading the forums about a failure of the ding the internet forums about a failure of the Garrett bolt design that held the two halves of the turbo together. Eventually the turbo failed catastrophically, and it was determined the bolts had loosened to the point the compressor side blades had impinged the housing and flown apart! After a lot of arguing and legal threatening of Ford, it cost them a new $12K powerstroke motor.

I'd quickly get a second opinion elsewhere,

Cal

 

Never heard of that problem - I would for sure get another opinion ASAP.

 

Your SA is full of crap, my 535 with 8000mls make no such noise.....get a second opinion, fast!

 

OK Thanks, Pretty much confirms what I already thought. Just wanted to make sure I'm not crazy. I think Turbo's are a little new to BMW and some of the first level techs don't understand it much yet OBVIOUSLY. I think it frightens me that I know more how this works than they do! It's the type of response I thought I'd get taking the car to Joe's backyard garage, but not BMW !!

 

I second that. Every since i had my car in the shop for a "electronic malfunction", i notice mine does the same. Mine does it regardless if the heat or air is on or not. It also makes a rather different sound when running and parked. I compared to another coworkers 535 and we both could tell the difference. Who knows!!