have all the normal "wear" parts been replaced- plugs, wires, cap, rotor, etc?
sometimes a $50 tuneup will clear up some really perplexing problems.
how's the fuel pressure? are the injectors good? i think those years had that extra injector for cold startups that shuts off shortly after startup- which sounds like about the time your car dies. if the fuel pressure or some of the injectors are weak, then as soon as the 9th injector quits firing, it could lean out and die.
could be a bad temp sensor, as well, causing it to run too rich when it warms up and killing it- kind of like the choke sticking on in a carbureted application.
you don't plan sincerity.
you have to make it up on the spot.
wanna hear about 20 years ago when i was too smart to know any better?