I have a 2001 A4 with 67k miles on it and recently my turbo (at least i'm fairly certain it's my turbo) has been making a noise that comes and goes, with varying degrees of severity. it sounds like ringing & it gets worse with the temperature (it's been 0 and below lately). but even after the car is warmed up it still comes and goes....do i need a new turbo?

 

uhmm well my brother has an 02 gti with the same engine and ive noticed that noise 2 and i belive its a hose because we changed some hoses on there and its gone now....
plus dieing turbos are usually a dentist drill sound not a ringing ..sooo im pretty sure its not ur turbos but i could be wrong go get them checked

 

I don't really know anything about turbos but I'm not completely car retarded. Is there any sure way to tell whether it's my turbo or not? The noise starts if I just turn on the accessory power and the speed/volume of the noise is completely independent of anything I do...except it seems to fade when I make sudden movements (hit a bump, turn tightly, etc).

 

You can grab the propellor shaft of your turbo and wiggle it checking for shaft play. If there is none, that is your ideal situation and it isn't your turbo going bad.

 

You never said what kind of noise, & when it comes & goes.
Does it do it under throttle, or at idle?

Usually is the turbo is going, it's going to make bad noises any time you hit boost.

 

I have a '00 A4.. thats funny you mention that problem cause my turbo does the same thing..
but it isn't really too much of a ringing at all. It's more like a rattling noise but it's under throttle not at idle.. I don't think its too much of a problem. you shouldn't really worry 'bout it.