Hello all. On two different trips today, my CMS started making a high pitched squealing noise that seemed to be originating from the back of the vehicle. I muted my speakers, but the sound persisted. I parked the car and got out to attempt to identify the source of the sound, and it seems to be coming from beneath the rear passenger side right by the wheel.

Any insight?

Here is a video clip of the sound

Thanks!

Update: Drove around for 20 minutes today and the sound was not present. Stopped by the dealer anyway and my SA said it could have been a tensioner or potentially the water pump. He also said it may have been due to the 100° heat we had yesterday. I guess I'll just keep an eye on it.

 

There also could be an air pump at or near the tank associated with the evaporative emissions control system. I think these are called 'leak detection pumps'. Have not heard this sound myself, and I don't know for sure if our cars have these.

 

sounds like a bad Fuel Pump

 

I agree with this guy

 

Wouldn't be a tensioner or water pump if the sound is coming from the back end... Unless your Mini has the rear engine option...