whats causing the problem

To check for a bad fuel pump, you need to check for power and ground of the fuel pump when trying to start the car. If you have those signals, check the fuel pump pressure.

if the engine light came on i would get a diagnostic it may be a sensor causing your car not to start thats the least expensive thing you can do and it will give you the best outcome.

Wow, sorry I didn't see this sooner - if it starts and then immediately shuts off, look for the Security light on the dash. If it's lit or flashing, it might be the theft deterrent system (PASSLOCK). If so, it could be a bad ignition cylinder ($50-150), a bad Instrument Panel Cluster ($300-600), or possibly a bad Powertrain Control Module (not sure the part cost there). I've had 2 Instrument Panel Clusters fail on me.