the car is a 1999 taurus wagon. it starts and runs great, but, it will occasionally crank until the battery dies but doesn't start. if the car sits for a while it will start. the fuel rail has fuel. when it won't start.

Does it have spark?

How much fuel pressure does it have?

Is there an anti-theft/security light flashing?

Do you use the same key all the time or a couple of different keys?