Whining noise when cold - sounds ill-lubricated (?)

[Moto-Mucci]

The car does this whining noise at certain vibration frequencies while moving. It sounds like the humming sound of metal friction when it's not lubricated enough. It's a constant fade-in / fade-out humming noise - not sporadic. The sound goes away after it's fully warmed though.

Any ideas?

[neighborhood]

where's it comming from? Check your wheel bearings.

[Moto-Mucci]

Upfront somewhere.
I'll check them out. Thanks

[E30 Cabrio]

I think my Alternator is starting to do that.

If you turn up your heater/accessories, does it become louder?

[Moto-Mucci]

Nope. No change there.

[Moto-Mucci]

Found out I can get it to make the noise sometimes just by revving the car in neutral

[cferb]

I think I have the same noise, not sure what it is either, is it kind of a fade in and out every half second or so?

[Moto-Mucci]

Yea, sometimes it'll go on for a couple seconds max.

[scabzzzz]

First things that come to mind are power steering, and wheel bearings.

But probably power steering. Now its getting colder, if your power steering fluid is not as "effective" in viscosity as it once was, it wont lubricate like its supposed to until its warm and has been moved around in the system first. Drop some Lucas in there.

[Moto-Mucci]

Sounds good. Thanks

[Moto-Mucci]

Changed the PS fluid and still making this noise. If anything, it's worse now.
Checking through the receipts, the wheel bearings were done recently.

[MrWizard]

Kind of hard to guess without seeing and hearing it in life.

Does it change with clutch pedal pressure?

Are there any signs of belt or metal dust around any of the pulley etc?

[Reign]

No one has mentioned it yet, but when it gets colder your fuel pump has to work harder. When the fuel pump is old, it will start to make a humming noise as the weather gets colder and colder. It will make the noise mostly at a cold idle. This can eventually cause a huge issue. Get your car checked out and address it quickly. Honestly though, no one can tell unless they actually check your car out themselves.

[Moto-Mucci]

It only happens when the clutch is engaged.
It happens in all gears, and always around 2k RPM.
Would something cause the fuel pump to always hum/whine at the same rpm?
It seems like it would be something rotational.

Also, it will do it at a stand still when revving it to 2k, so wheel bearings are out.

[jlevie]

Alternator, PS pump compressor clutch, or any of the belts are possibilities. To help isolate the source, temporarily remove the PS and compressor belts.