Strange noise

SCOTTTAY

MEMBER
2006 AUDI A3
2.0L
3 CYL
2WD
MANUAL
160,000 MILES

I have the car listed above tdi sport. When the car has been driven for a bit and is warmed up sometimes under acceleration I get a noise appear. Only way I can describe it is as a whining noise. As you accelerate more the pitch of the noise gets higher and sometimes will totally stop. But when I change gear it starts again when I accelerate. From what I have read it is the turbo, but also been told it could be a bearing of some kind. Any help would be great.

1 Reply

SCGRANTURISMO

MECHANIC
4,897 POSTS

Hello,

If the sound you hear sounds like a "swoosh", then all's that is is the sound of the compressed air topping out as you change gears. I have a centrifugal supercharger on my Mustang and it is almost identical to a turbo, the only difference being a turbo spins its compressor wheel with exhaust gas and a supercharger uses the serpentine belt to spin the compressor wheel. You will also get a whine when accelerating from either one these power adders as the compressor wheel rpm's pick up. Want to do something fun? Go to a turbo/supercharger rpm calculator online and see how fast it's compressor wheel spins. The answer might shock you. I hope this helps.

Thanks,
Alex
2CarPros