Oil pressure icon blinking on '91 200Q

[James Desveaux <desveaux@ucla.edu>]

Today I finally fixed the bothersome worn brake pad icon problem.  Went to
my friendly german auto salvage yard in Watts and pulled the female-side
brake sensor plug-in from an S4 and spliced it in, replacing the defective
one.  About 2 hrs later, I drove over a pretty decent sized bump and heard 3
beeps.  This time the icon was red, and the oil pressure oil can started
flashing.  THe oil pressure gauge was reading fine (between about 1.8-2.2
bar at idle and up to 5 bar at speed).  THough I figured this is another
typical Audi electrical gremlin, I pulled over, checked oil, etc.  After 3k
miles since changing it, oil is exactly full (with none added) and there are
NO leaks.  I restarted the car, and the big OK lit up, and then the radio
station.  A few seconds later, the beep returns with the red icon.  I keep
driving down Bundy Drive (yes, THAT Bundy), and a short time later (hey, the
beep is gone), I notice that the radio station frequency is illuminated in
the display.  No more beeps and icons.

Question:  Anybody had this happen to them?  Is it a corroded connection at
the sending unit, or some such thing?  The car has 91k on it now, but
everything's pretty much spud on it.  I bought it at 88k and did the usual
precautionary things, such as t/b, w/p, front main seal, etc.  Any advice
would be appreciated.  

- Jim