[Hulton]

Howdy,

For a few days now I've been having an issue with my 2006 E90 ventilation system. Whenever I start up the heating in my car there's a lot of weird sounds coming out from the air vents, some are seriously loud and scary. I've recorded some of them:

First one is some kind of weird howling while the 2nd one is literally screeching.

https://clyp.it/1a2knnnn

https://clyp.it/lvkiavkz


Does anyone have any idea how to fix that easily?
Makes using the heating and driving really uncomfortable.

[Wolf 335]

Does the noise change when increasing the fan speed or while making turns?

First order of business would be to remove the blower fan from under the glovebox and apply some oil on the base of the shaft and onto the bearings.

I used turbine oil and it worked great.

[Hulton]

Yes, the sounds start somewhere at the middle fan speed and actually tend to get quieter with higher speeds while changing the sound pitch at lower setting.

Allright, will do that soon, and let you know if that helped.

Thanks a lot!

[Efthreeoh]

Just replace the blower motor. Once the bearings start making that level of noise they are pretty much trashed. Oiling them will temporarily solve the noise issue, but eventually the fan blade will start to scrape on the bottom of the fan housing.

[MightyMouseTech]

Worn bearings is also what causes the evaporator to start leaking. Brass dust from the bearing reacts with the aluminium of the evap.

[Hulton]

:O Thanks for all the answers. Allright, I will take care of replacing that part in a few weeks then.
For now I just want to solve the issue temporarily before this sound makes me end up in
psychiatric hospital

[Captain Kudzu]

https://www.fcpeuro.com/products/bmw...-64119227670-1

It was pretty easy to change. Mine was squealing. Changed to this one and it is nice and quiet.