My R56 jcw is making this weird whining sound almost like a siren? I’m assuming it’s the turbo but want some second opinions before i go snag myself a new one and have it be something else. Only mod I have is the Forge Motorsport BOV. There are no CELs or DTCs

Video of Sound:

 

Almost seems more directly related to RPM, so I'd check the belt / alternator / idler pullies.

Can you get the noise to change by turning on the AC?

I feel like if it were the turbo it might be much more undriveable...or is it?

 

I haven’t tried to drive it beyond 15-20mph the night it started doing this so i really don’t know how drivable it is. No change with ac on or off

 

well you'd pull a CEL if it were that serious. just drive it and see what happens. probably a pulley, belt.

 

Took it to mini and they have diagnosed it as a turbo. The impeller apparently was falling off...

 

hahaha. That's serious. Check out JMTC turbo. That guy knows his stuff. Guess it doesn't throw a CEL. Probably ran with low oil. I always keep my oil topped off.

 

Oh no that's not good :( Most of the time its the oil seals in the turbo or the wastegate.