Im the proud owner of an 01 1.8t A4. Ever since I bought it a year ago, it makes a loud whine when it starts, which goes on for a few minutes. I never thought anything of it until recently (couple weeks ago) when i bought it in for an oil change and one of the pit crew mentioned it might be a problem. Last week it started to make a noise when i accelerated, almost like theirs air sucking in from somewhere. Only happens when i accelerate past 2500 rpms, and doesnt make the sound when im not moving. looking for any advice; im not sure where to go from here.

 

im pretty sure the sucking sound is the turbo; forgot to mention that

 

Hope you don't mind, I moved your thread to the B5 A4 section where it is likely to see more traffic and general helpful replies.

If there is a loud whine after a cold start for a minute or so, that might be your Secondary Air Injection (SAI) pump going bad.

Sucking sound could be a number of things, like a torn rubber hose causing an air leak. You could perform a "boost leak test" to check for torn hoses.

 

Replace all of your vacuum hoses before you do anything. It's the cheapest option.

Your car most likely needs it anyway and it may fix your problem.

There are some DIYs here on hose location, etc.

G/L