I have a '00 1.8t Quattro, and lately on startup, I have been getting a SEVERELY high pitched noise coming from the turbo that lasts between 10-30 seconds. When it comes down from the high pitched noise, it decelerates and makes a final, even HIGHER pitched noise for a split second. This cycle also happens occasionally when driving, though it lasts between 2-3 seconds. In between these crazy noises, it drives perfectly fine. I know that the first thing that I should look for is a problem with the DV, which I will do, but has anyone had this problem? I am curious to know exactly what is going on.

 

search for problems involving the secondary air injection pump. it is not uncommon for it to seize up causing a noise kinda like what youre describing.

 

could it also be the turbo dieing? i ahve this same thing and it happens almost every start up now.. seems like it spools for 30 seconds after tis done Doing its thing the rpms drop back down then about 5 min later it spools again for less that five seconds.

 

aaaaaeeehhhhh, I agree with zadeluca. sounds like a secondary air pump issue.