Need Help with 4000 fuel injection system

I'm hoping someone here can help me with this maddening problem. I'm having trouble with the vacuum system on my 1985 Audi 4000S (1.8liter 4cyl fuel injection). The problem is with the air flow sensor plate which seems to work
OK after a thorough cleaning, but quickly develops a dirty carbon-like film and starts sticking after only a few minutes of run time. I've cleaned the entire system, including replacing the air filter, fuel filters, put on a new intake air duct, and re-centered the plate. The car runs OK when I manually move the plate, but as soon as I put it all back together, it soon starts missing, and quickly gets all gunked up again. It's starting to dirve me nuts. Can anyone help me out there? Could it be a sabatoge of the fuel (although I can't imagine how it would be connected)? The reason I ask is beacuse the car was running fine, and one day I parked it for an hour & when I came out to the parking lot I noticed a paper wadded up in the exhaust pipe. I removed the papaer, and guess what? the car wouldn't start! Maybe I should plug up the exhaust again, huh? (LOL). Any thoughts would be appreciated. TIA Cappy
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Where is the hose for the crankcase breather going to? This is probably where the fumes are coming from that might be causing the sticking gummy stuff. What does the motor oil smell and feel like? I am thinking thin with a gas smell.
Still have the locking gas cap so no one can add crap to the gas?
Change your oil and see what happens.
later, dave Reminder........ Before you criticize someone, you should walk a mile in their shoes. That way, when you criticize them, you are a mile away from them, and you have their shoes. Frieda Norris
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Are you sure it was paper? Could your catalytic converter have taken a dump? What happens is that the paper-like thin metal substrate falls apart and gets blown 'downstream' throughout the exhaust system. It can also effectively *block* the system, which might cause this kind of symptom. Unless your cat has been replaced, this is worth a look. -- C.R. Krieger (Been there; done that)
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