I've had dumb problems with the distribtor and from bad grounds that have made the car bog, shut off, tach jump around, car just do tons of weird stuff,
so check all your grounds and try a new distribtor if you have another one laying around if not then clean the rotor/cap
when you have bad grounds anything can happen my car would not turn over and I use to have my cooling fan turn on when I turned the key to on but once I moved the ground so it had good contact it would start up and stop turning the fan on =) as with TONS of other dumb things
damn gounds I've had problem after problem with them till I replaced my wires and added a few more going from the battery to the distribtor
Jeff