Strange high pitched whine/hum

[ba3bas]

Recently been hearing a high frequency whine or hum from the middle of the car.
Can hear from inside and outside.

It's right in the middle of the car behind the seats.

No fault codes.

Thought it might be the fuel pump but then noticed that if I turn the steering wheel the pitch changes sometimes.

I can only hear it when I'm still.

Any ideas?

 

[nightyard]

is it when driving??

my old car did it a little in first gear.

 

[pbachran]

Cat caught in the driveshaft?

 

[ba3bas]

No just when stationary

It's not the first gear whine either, that's normal

 

[aquazi]

stereo -interference?
dvd drive (for Nav)?

 

[mad4slalom]

power steering pump ? some minis have a really noisy psp, mini, bmw ? same part pos ?

 

[domsz4]

power steering pump ? some minis have a really noisy psp, mini, bmw ? same part pos ?

Zs don't have power steering pumps its a servo on the column. i read stories about the power steering having harmonics when its used which you can sometime hear. i know mine does it now and again. cant remember the reason why it does it. It also makes soft little clicks. its something to do with the modulation that drives the motor.