Whining sound below 20mph

[The Database]

Originally Posted by Richbot

That whining sound is generated by members of M3post.com, you can't hear it above 20mph due to road noise.

lmao hahahaha

[neilvosko]

did you change the PS fluid?
having same noise on the 335i

[1MOREMOD]

its your car crying out for a SC.

[M3Denver]

Check your pumps... Power steering, fuel etc.

[tailgate1234]

I had the exact same problem, same whining noise between 1-2k rpm. Asked that the dealer look at it especially the power steering fluid and power steering. The dealer couldn't hear the noise and wouldn't do anything further.

[tibra1]

Now the next question is why were you low on power steering fluid?

Did you check for leaks..sometimes their can also be leaks internally thru the seals of the steering rack or pump

[OC3]

I got that same sound a few days ago, and checked the power steering fluid level and, sure enough, it was very low (barely touches the bottom end of the center dip stick). But, that's the "cold" level. Not sure how much it would've risen after driving it hard.

tibra1, the filler cap has a vent hole on it, through which the fluid leaks. Happens a lot to cars that get tracked (or, otherwise, driven hard) when the fluid heats up/boils. So, a lot of us keep the cap covered up with a towel & ziptie.

Anyhow, in checking the fluid level, and I was taken back by the color of the fluid, as follows (excuse the sh*tty iPhone picts). First is before filling it up, and second is after (& driving around for about 15 min's).

A mechanic and a SA (these 2 people at 2 different BMW dealers) told me that the discoloration is due to cavitation (triggered by low fluid level). Taking the car in for inspection in about an hour. Will post findings/results/assessment.

.

[OC3]

Sh*t, flushed the power steering fluid system & re-filled it, but the noise is still there, and even louder now. >:I

[OC3]

I tend to agree re: it being power steering related.

I've got a track day this Sunday. Need to decide to track or wimp out.

[M3zcp1]

Was this ever resolved? Was it remaining air in the system?

[m3an]

Originally Posted by OC3

I tend to agree re: it being power steering related.

I've got a track day this Sunday. Need to decide to track or wimp out.

did you cycle the pump turning the wheel back and forth after filled? Sounds like it def got too low and allowed air in the system



edit: see this is an old thread so I'm sure it's figured out

[OC3]

Originally Posted by m3an

did you cycle the pump turning the wheel back and forth after filled? Sounds like it def got too low and allowed air in the system



edit: see this is an old thread so I'm sure it's figured out

Of course (cycle it).

The dealer did the fluid flush & re-fill, but as expected, couldn't figure out what exactly was causing that noise despite extensive inspection and a 30 minute drive around the next day with SA & mechanic.

Went to a track the following day and (as the fluid was topped off & all new) ran the first session (6 laps) without covering the reservoir cap with a rag & zip-tie. I couldn't tell due to the wind noise while on the track, but when I got back into the paddock, holy sh*t, the noise was there with a vengeance. Every little turn on the steering wheel was accompanied by that whining noise.

Opened the hood and, sure enough, the fluid had splashed everywhere in the engine bay and, when the reservoir cap was opened, the fluid was barely visible at the bottom neck of the reservoir. I had bought a can of 11S fluid, so (after the car cooled down some) topped it off, zip-tied a rag around the reservoir cap.

Went out & finished the next session, came in & drove around the paddock and the noise was gone.

Had 10 more track days since then, and the noise hasn't come back. But, at Streets of Willow, after drifting thru the skidpad area (i.e. screwing around with the steering wheel) on every lap, I lost power steering. But, it came back after an hour of cool down. This car in track application needs larger cooler for it...

[sensi09]

I have the exact same noise under 20mph, but it goes away once the car is warm. I was planning to make an appt at the dealer, but by the time I get there the noise would be gone.

Anyhow, thanks for this. I thought it was just me being listening more closely since the warranty is almost up. Doesn't the dealer check fluid levels during oil changes? The sound became more apparent after my last service which was a few weeks ago.

[sensi09]

Originally Posted by JCE

I had this same noise....it was the power steering pump. They replaced it.

I ended up having the power steering pump changed too.

[polonus]

Originally Posted by 1MOREMOD

its your car crying out for a SC.

Mine has SC and is whining too. What else does she wants?

Originally Posted by JCE

I had this same noise....it was the power steering pump. They replaced it.

Originally Posted by sensi09

I ended up having the power steering pump changed too.

Did you have to pay for it? How much was it?

I hope topping off reservoir will quiet her and that will be the end of the story. I just bought a new battery, two rear tires and changed oil ($1100 total) and that should be enough for January, right?

[2011_M3]

Originally Posted by creepy coupe

I would say definitely engine driven and not tranny.

Anyone know if you can knock a DCT into "N" while coasting?

Move and hold it to the left and it show go into neutral.