No Start/Hard Start

[Jon Moritz <jmoritz@mail.med.und.nodak.edu>]

I jinxed myself ...I said my car was reliable... now this:

Started my '92 100 non-q and drove to work like any other day.  5pm time to
go home, engine will crank but not run... fool pump seems to be working,
give up after 15 minutes trying to start it (no tools with me and 34 miles
from home), hitch ride home.  this morning, drive to work in my vintage tin
('56 Dodge truck), park next to car. Try to start it, and it runs! albeit
shitty, turn off and try to start again, runs, but really rough.  Did my
vintage tin embarrass my Audi? Any Ideas? where do I start diagnosing this
one?  

(and now I have to deal with having both vehicles at work ... *sigh*)

TIA
Jon
Jon Moritz
University of North Dakota - School of Medicine
'92 Audi 100 97.5k mi
In the Audi wasteland of NW Minn/ NE Nodak