Hmm. Being a TBI engine it wouldn't seem like there are many things besides the computer itself that would cause fuel and spark not to be present. Normally they are run on somewhat of a seperate circuit. If it does it again, check and see if the fuel pump still primes the engine when you turn the key to the on position. You should get about 2 seconds of priming.
If it were a later multiport system, I would guess something like the crankshaft/camshaft position sensors as they help control both fuel and spark and will elimiate both.
A faulty oil pressure sensor might cause this depending on the car. Some vehicles only wire this fail switch to the fuel source but its possible, as it runs through the computer, that it would also eliminate spark in the event that the computer wasn't reading anything from the pressure sensor.
A buggy computer can also be a culprit. If you have time, Id get a wiring diagram for this car, and look for any circuit the spark controller and fuel supply have in common. Sometimes they share a power relay or both route their power or signal source through a common sensor.
Its kind of hard to say as no engine codes were thrown correct?
Fingers crossed for now I suppose. Let me know of any other info you have.
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