loose or damaged wires in ignition system.intake manifold vacuum leaks in intake or hoses. or its not getting fuel to injectors.
more than likely it is your alternator, have it tested.
check fuel filter,sounds like your not getting fuel,
fuel pump
Diagnosis: Engine Won't Start or RunCheck related link below
If the theft system light is flashing...try to start car,when it starts and then dies,leave the key on for about 10 mins. until it stops flashing.Turn key off,Now start the car as usual.
car dies when running then hard to start ,if it will start
If engine starts, Fevs, then dies. Check for diesel fuel in gas tank.
My 2001 Bonneville did the same thing yesterday...it needs a new alternator.
Start the vehicle.. and disconnect the positive terminal of your battery.. if the engine dies.. your alternater needs attention.
reincarnate your battery dudes XD
Mass Airflow Sensor
oxygen senser