The problem sounds like pass key malfunction. The security system shuts off the injectors if it doesn't get the signal from the lock cylinder.
PASSLOCK SECURITY SYSTEM
I will start by telling you that the PASSLOCK security system is engaged only when starting. It will not cause the engine to stall.
The most common intermittent no start problem I am aware of on this system is in the ignition lock and housing.
This system works by the sensing of the ignition lock being rotated. The ignition lock in this vehicle is open. It has been very common to have excessive grease (graphite) in many cases to spray in the housing blocking the magnetic field. Thus, the computer cannot sense the rotation of the ignition lock.
Remove the steering column shrouds. Once the column is exposed, on the top of where the ignition lock is mounted there is a hole. Insert the key into the lock. Rotate the lock to the ON/Start position. Insert an ice pick awl into the hole and pull on the lock cylinder. Once you have removed the lock cylinder, clean the lock with brake cleaner and wipe off. Do the same to the housing it fits into. Reinstall the shrouds. Insert the lock into the housing and rotate and push inward until the lock goes back in place.
This is something the dealers are not familiar with and yet is very common.
There is no special ignition key and the security is built into the lock and the housing with a magnetic field. The vehicle's computer senses the rotation of the lock and thus fuel is delivered.
This will be the cheapest thing to try.
To reset the pass key, turn ignition on to run position and don't crank. Leave key on for 10 minutes before cranking.