I own a 1999 A6 Quattro with the 2.8 - V-6, and am going through the aging blues. I just recently replaced the passanger side Cat Converter a month ago, only to have the drivers side fail thai past week. So in preparation of replacing it, I decided this would be a good time to consider some mods. And of course, as things usually go, the car would not start the other day. So, I am hopeful that someone has dealt with no-starts on these cars, and that I can share what I learn as I go through the process.