Need help with GTV oil pressure problem

[Frank <fca@xxxxxxxxxxxx>]

Driving to work this morning in a '69 GTV, I suddenly noticed that the
oil pressure guage was flickering wildly between no pressure and normal
(almost full) pressure.  Then it dropped to no pressure whatsoever and
stayed there.  I pulled over and shut off the engine, checked the
dipstick and it looked normal (bathed in oil).  The red low-pressure
warning light comes on when you first twist the key and goes off a few
seconds later.  The guage has always been pretty normal until today.  In
any case, I took my chances and drove the rest of the way - about 3
miles without exceeding 2000 rpm while keeping an eye on the temperature
guage (which stayed normal) and pressure warning light (which stayed
off.)

I just checked the dipstick after 4 hours of rest and the car has plenty
of settled oil.  I started it and took off the filler cap and observed
oil blowing out the filler.  I ran the engine at idle with two low
throttle blips then shut it off.  I checked the dipstick hoping to see
it bathed in oil as an indication of a working oil pump, this was not
the case - the dipstick still looks clean above the oil level.  Is this
normal?  Must I run the engine longer or harder for the oil to travel up
the dipstick?

I guess the real question is, is this a real oil pressure problem or
just a flaky guage?

- -Frank (Cape Cod)

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