Assume it's an ignition problem.  To verify this, disconnect the cable
from the center of the distributor and hold it about 1/8 inch from any
part of the engine (use gloves so you won't get zapped). Have someone
crank the engine and see if there is any spark.  If there isn't, you
then have to find where the B+ (12 volts) is not being applied. Use a
multimeter or neon light to determine how far the B+ is getting.
Start with the + terminal to the ignition coil, then work your way
back to the ignition switch.  It's best if you have a wiring diagram
for your car so you are not guessing as to the circuitry and don't
have to resort to the "shotgun" repair method where you're sort of
guessing what component is bad and then replacing it, finding that was
not the problem. Intermittent problems are tough; you have to try to
recreate the scenario where it seems to fail, if possible.  I like it
when they finally become a 100% failure, so then you can track it down
without a hassle.

I have had that same problem with mine and was told its the relay for
the fuel pump or the auto shutdown relay, seems the plug that goes into
the relay gets dirty and doesn't allow enough voltage to get through to
the pump.
I was told this and that this was a common problem with this year and
the type of plugs.
I tend to believe it as I know I had to clean up these contacts a few
years ago.

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