My car turns over and starts however after two seconds it dies?

What is your question?

It started yesterday out of the blue. I can start the car and it immediately drops in idling power and shuts off. It will not stay on. when i put the key in the start position before ignition, there is a whirring sound for two seconds. I really need help as this is my only car. It is a 2001 toyota sienna minivan.