My 98 WRX STI4 has had a noisy turbo for the last 8 months.
Nothing much really, just a noticeable whirring off the thing when standing or blipping the throttle at low revs with window down.
Maybe the sound is getting a little worse, or maybe it's just the cold damp air that exagerates it.
Anyway I thought I would ask if anyone else has experienced a similar problem, and if so did it imply eventual turbo failure, or is it just one of those things that some of them do after a while.
Is turbo failure likely to risk damaging the engine (if so I guess I should swap it out before it goes pop - any ideas on cost ?).
2 independent garages have been aware of the problem, but didn't seem overly concerned.
The engine has done 57K miles, the last 8months i did about 12K miles.

I have had a Blitz airbox on for the last 40K miles, so it's not something that happened since I ditched the standard airbox.

Boost and performance has not been problematic since this sound occured.

I would guess it's just one of the blades is slightly damaged and that's what causes the 'wirring' sound.

Any help or advice will be appreciated.