Whistling noise

[iStang]

I'm worried about a high pitch whistling coming from my car (20000mi). Unfortunately I can't located the source precisely. The noise appears at 30mph and is still noticeable at 50mph, but then wind noises cover the source. It seems not to change the frequency when driving faster. It's not the serpentine belt because it's not rpm related and a defective gas pump makes a different noise. I exclude wind noise too.

First I thought it is coming from my chin spoiler which was a little bit loose. Maybe it's brake disk related. I noticed on one disk I have a pretty deep groove. But there is no unusual friction or unusual heat coming from the brakes after driving.

First time I noticed this whistling noise was after I had to cross a deep puddle, but it may be only be by coincidence.

Thanks for your ideas

 

[Shiroelex]

Throwout bearing maybe? Does it go away when you push in the clutch? If not, then take a piece of wood and set one end of it on your alternator housing while the engine is running. Put your ear to the other end of the wood and llisten for the same noise. If not there, try your AC compressor. Those were a few that had developed over time in mine. Good luck!

 

[iStang]

When I drive and press the clutch or put in neutral nothing changes. AC I have to test and I will also listen to the alternator.

Bearing? Do you mean the bearings of the transmission?

 

[Shiroelex]

Kinda. The throwout bearing is with the clutch. Another possibility could be the pilot bearing, if you can hear the noise from more of the middle of your car. Underneath, as well.