oil pressure warning light - danger?

[Dixon <biwltud@bellsouth.net>]

I would appreciate any advice as to the immediate danger and subsequent
debug of an intermittent auto-sense oil pressure light problem.  Here's
what I know so far:

*  It's an ''89 100 (NF engine) and the light activated several times
within the last week.
*  The "OK" confirmation registers when initially turning ignition ON.
*  Occurs when the engine is warm/hot (oil temp. gauge registers ~100C
but I haven't checked its calibration).
*  When cold, the oil pressue gauge registers from ~3 bar (idle) to 5+
bar (pegged w/med.-to-heavy throttle).
*  While the engine was hot and parked in my driveway today, I gathered
these pressure readings at multiple rpms.

idle               1.6-1.8  (gauge seems to jump around a bit)
1k                2.0
2k                3.5
3k                3.8
4k                4.0

*  When I did the driveway test, I followed by stopping/starting the
engine three times.  Each time, while in Park, revving the engine to
approximately 3k rpms would cause the light/chime to activate.
*  At idle, the oil pressure gauge jumps around a bit with 1.6 bar being
the lowest pressure that I observed.  Each time that I have noticed this
while driving, I try to keep the rpm above 1k to keep the pressure up,
hoping to avoid damage (since I don't know what's going on!)..

I checked the Bentleys and plan to test the oil temperature and pressure
gauges once I obtain the necessary resistors.  I don't have the
equipment to test the sending unit/auto-sense electronics.  I had the
oil changed at a local shop and believe that I am running 10W40 (mild
Atlanta spring temperatures).

Any information/suggestions are most appreciated.

Regards,
Adam Dixon
'89 100 - 132k