> I have a 1987 Vanagon Syncro with 150K miles.  I'm looking for
> info from anyone who may have experienced or heard of
> something similar to, what I am experiencing.  After driving any
> significant distance at high RPM, when downshifting, the oil light
> & buzzer turn on.  This may last 30 to 60 seconds (or so) and then
> they turn off. It happened occasionally at first (beginning almost 2
> years ago), but now occurs much more frequently.

This happened in my '91 almost all the time when the engine was
at about 2000 to 2500 rpm. After much head-scratching and
testing by me and several mechanics at different garages, one of
them finally hit on the cause: a check-ball assembly near the oil
filter which if I remember right is a bypass system to deal with a
clogged oil filter. The check ball was sticking at lower rpms and
the pressure at the sensor was a bit too low. The parts were cheap
and it didn't take too long (or too much $$) for the dealer's mechanic
to fix it.

- Scott
  former owner '91 Westfalia Camper