This could be tappets or maybe the vacuum pump. I would try, removal of the vacuum pump operating pushrod to determine which it is. The tappets can be repaired if you're tight!
http://www.clubgti.com/forum/showthread.php?t=76499
More vacuum pump info...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.