I had just turned to get on the freeway on ramp yesterday when my 06 MCS started making a noise like someone stuck a stick in a fan. I quickly messed around with the AC controls and finally turned everything off and the noise seemed to stop at the same time. I wasn't sure though as I was accelerating onto the freeway . After that everything seemed okay and when I got off the freeway, I turned the AC back on and no noise. Anyone have an idea what could have caused the noise? I don't want to mess something up. Thanks.

 

Might look at serpentine belt ider bearing.
Could also be the fan motor bearing.

 

check the PS pump fan, when mine was going out it only seemed to make noise when the a/c was on

 

I'm new, sorry but, how does one check the power steering pump fan. Thanks.

 

there is a small electric fan center of the car just past the oil pan. it blows upward to cool the power steering pump. it only comes on when your radiator fan blows on hi(when its hot or whenever the a/c is on).my PS fan was making a terrible loud noise due to the bearing going out. just reach under the front of the car and touch the fan(while it is on), and feel for a odd vibration. if it is the source of your noise you will know immediately.

 

OK. Thanks very much. I'll check it out.

 

that the manufacturer's warranty would cover the PS fan? Mine is good till the end of this month plus the car has a BMW CPO warranty as well.

 

not sure worth a try. but if not and that is your problem, let me know and i'll tell you how to fix it for 30 bucks or so

 

had somehow gotten lodged underneath the car next to the exhaust pipe which would explain the racket. I guess the drive home wore off enough to silence it. I'm relieved and a little embarrassed. Thanks to all for the replies.

 

Nice hahaha

 

Yeah. Glad I looked before taking it to a repair guy. I doubt that "stick removal" is covered by warranty!