Valves, checking
WARNING: This page is about a different car, the 2010 Audi A8, 2009 Audi A8, 2008 Audi A8, and 2007 Audi A8. However, it is still accessible from the selected car via links, so may be relevant.
- Check valves at stem and seating surface for traces of wear.
- If there are clear traces of wear, replace valve.