Audi 80 Starting Problem

[Brame1 at aol.com]

Good Afternoon,
 
My 1991 Audi 80 had a starting problem and I installed new Bosch  plugs, 
rotor cap and distributor which seemed to solve the problem.
 
It started very easily and ran very strong.  This past Thursday, I  added a 
can of BG44 to half of a tank of fuel, filled it and drove another 125  miles 
with no problem.
 
Saturday evening I drove approximately 22 miles to a church sponsored ham  
and oyster dinner in Washington DC.  I parked on a downhill slope.   After 
shutting the car off, I realized that I was not far enough away from a  driveway 
entrance and tried to restart the car.  I could not get it  started.
 
I went into the Church for dinner and returned approximately an hour and a  
half later and still could not start my car after numerous tries. I tried  
holding the accelerator to the floor: that did not work.  I tried letting  the car 
sit for another hour;  that did not work.
 
I decided to just lock the car and come back, Sunday evening; which I  did.  
The car started immediately but did cut out a couple of times before  I was 
able to place it in Drive and get home. 
 
It ran very well until I got into my driveway and tried to turn it around  
when it cut out again .I tried to restart without any success.  I was able  to 
push it into a spot on my driveway.
 
I just went outside at 2:15 PM EST and started it.  It cut out a  couple of 
times but restarted with no problem.  I let it fast idle for a  little bit but 
when I took my foot of the accelerator it cut out and I was not  able to 
restart.
 
Any ideas or suggestion?  Fuel Filter?(Where is it?)  Air  Filter?  It has a 
K&N filter that has not been serviced in a long  time.  Oxygen Sensor?
 
The Bentley Manual does not show a fuel filter and does not provide good  
instruction on getting to the air filter.
 
Thanks In Advance for your help.
 
Nick Brame, CSA Darnestown, MD
(301) 840-5931
"Helping  People Make Smart Choices With Their Money"
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