Jess

Roverlike,
Thank you for your response. Replacing the four relay multi relay pack mounted on the engine management system to the left of the engine (when facing forward from the rear of the car) is the first thing that I did. That did not resolve the problem either.
If the airbag fault system is not what is causing the engine not to run, I am beginning to suspect that it may be the engine ECU itself.

David, I agree that it is a fuel issue. The engine consistently fires and runs for the three seconds whenever the engine ECU instructs the fuel pump to prime. But once the engine starts under these circumstances, it quits as if it is getting no fuel. The engine will not start and run when cranking the engine unless one gives enough time for the engine ECU to reset and instruct the fuel pump to prime the system again.

I am more concerned about what is causing the engine not to run (that is, why no fuel is being delivered except when the ECU instructs the fuel pump to prime).
After replacing the multi relay pack, I thought that it might be the crank sensor not sending a signal back to the engine ECU. But that has not resolved the issue either.

Any other ideas? Would it be worth having the engine ECU checked? Again, PSCAN showed no error codes for the system. But that might not mean anything.
Jess