Audi uses hydraulic (automatic) valve lifters in some engines. These lifters are noisier than
non-hydraulic lifters, so if you are used to the sound of the non-hydraulic, the lifters in the
Audi may sound loud to you. Every Audi I have owned (1985, 1993, 1998, 2001, 2009, 2010,
and 2018) all made some valve lifter noise. Best suggestion is take it to a good local Audi
mechanic (not necessarily at the dealer) and ask them to take a listen. A good mechanic will
take a listen for you at no charge. P.S. Most of my Audis were bought with 100K miles and
driven to 200K, the 1998 is still going strong at 250K.