Whirring noise from the engine bay

[jsllsj]

Hi All,

This afternoon when I started my M3 there was a whirring noise that was pretty audible from the cabin. I've never heard the noise before, but I thought maybe it was just the car warming up. I drove it around for a few miles, and the noise was mostly consistently there, but disappeared for a few seconds at a time. I captured it on video:

Any idea what it could be? My mechanic is closed for the holidays so I won't be able to take it in for another few days.

Thanks!

[MilehighM3]

Have you checked the level and condition of your power steering fluid?

[Vic311]

^Could be PS fluid if it makes more noise as you turn the wheel

To me it sounds like a pulley bearing

[Rshane]

Have you had your brake fluid changed recently? Kind of sounds like your brake solenoid working overtime. Just a guess, it's kind of hard to tell from the bid.

[jsllsj]

I just checked the power steering fluid and its at the correct level. I didn't change the brake fluid recently. Strangely the sound was completely gone this morning. I still made an appointment to get it checked out.

[thekurgan]

Not sure about the power steering, but I do hear a squeaky pulley or serpentine belt.

[Vic311]

Originally Posted by jsllsj

I just checked the power steering fluid and its at the correct level. I didn't change the brake fluid recently. Strangely the sound was completely gone this morning. I still made an appointment to get it checked out.

I am pretty sure it is a pulley bearing..moisture on a cold engine sometimes causes that noise. If its gone and you cant replicate at the dealer they will most likely do nothing for you.

[jsllsj]

Just got it back from the mechanic. He wasn't able to reproduce the sound and said it had to do something with it being a cold start and not to worry about it unless the sound is constantly there.