Dentist drill sound

I've read that it's a sign of imminent turbo failure. I hear a faint dentist drill sound as soon as I get off the gas, and it sounds electronic, not mechanical. It stops after a few seconds and is the same pitch and volume throughout. I'm hoping this is just some weird sound that comes with turbo engines. I have a rev D diverter valve that I'll be throwing on (I'm pretty sure I"m on the older one) this month.

So, you mean there is shaft play & the impeller blades are giving it a root canal? (Sorry for continued dentistry joke) or can you take the outlet hose off & wiggle the shaft to visually see any sideways play? The blades rubbing the housing can make a dremel/grinder noise. But maybe be more specific in description of what it’s doing, like it also loses boost.

There aren't any symptoms that the car is on its way out, but I was just browsing the forums and happened upon a thread that associated failing turbo with a 'dentist drill' sound. The sound is noticeable and I would rather know what it is. It just sounds like a high pitched dentist's drill or a long high-pitched beep (~2 seconds).

My 2007 GTI just started making this sound too, 112,000 miles. It comes on after the car has warmed up and has been driven 20 mins or more. The sound is mostly heard at moderate acceleration and is not dependent on speed. I'm hoping it just the belt tensioner and not the turbo taking a dump.


-RJM

Mine is always when I'm off the gas and it's for the same duration, same pitch, and same volume every single time.