moedip - Turns out there are no screens inside the fuel destributor on my '89 560 SEL. Just went and checked - nothing. Maybe they changed them in '89, which would explain why Phil coud not find them.
I'm back to square one. I had really hoped that this would take me closer. I am beginning to worry its something more fundamental, like a stretched/worn chain or bad valves. Somehow I think my fuel lines are fine.
1989 560 SEL (black/black)
2001 Audi TT Roadster (silver/grey)