Sorry about the intrusion of non-vanagon material, but I don't know where
else to look.  Just bought a 83 Rabbit.  Took to the shop for
maintenance--oil change, steam clean, alternator replace, battery replace.
Now, intermittently, at low rpm (less than 900) the oil lite and buzzer come
on.

Is this a voltage/electrical/sensor problem or a bad oil pump.  Would
appreciate any advice on how to diagnose.  I've already spent too much money
at the shop and will do this myself.