Hi there,

I just recently bought a 1998 Audi TT 1.8T.
Whenever I floor it the Turbo spools up, cuts out for 1-2 seconds, spools up again and so on. (Wavy turbo feeling)

Any suggestions to what might be causing this problem, and how to fix it?

 

Almost certainly a bad N75 valve buddy.
Had the same issue with my old 1.8T A6 (2002)

When I swapped the control to a MBC it solved the issue.

For how much a N75 or MBC costs it's worth trying that first.
Those were the EXACT symptoms I had, that distinct wavy feel, the N75 was cracked upon close inspection.

 

Oh wow, this forum is as dead as I thought, just noticed how old this post is, despite being on the front page of this forum.



I'm leaving, find somewhere that people still use.

Bye bye tumbleweedforums