1989 Quattro 90 engine Problems - Lifters??

[DNRLiss@aol.com]

I have not seen much mention of 1989 Q90s.  Are there many still out there?

I am experiencing an acute tapping in my engine.  The tapping has been getting
progressively worse.  It seems to be isolated to the valves.  There seems to
be significant vertical play in the thrid valve.  So my mechanic is in the
process of replacing the lifter set.  Should he do all of them.  Has any one
experienced a similar problem?  Additonally, my mechanic is advising using a
new, improved lifter that was referenced in a service bulletin - of coarse at
a significant premium!  I would appreciate anyones insight or condolences...

Ray
dnrliss@aol.com