2002 F-150 FX4 Triton V8 5.4L - Bought the truck three years ago and the remote start worked fine. Lately it usually will not start the truck, but it spins the motor over very fast. Tries 4 or 5 times them quits. When I put the key in it starts right away. My theory is something electrical is stopping it from running, but I have no idea how to diagnose it exactly. Any suggestions where to start?

 

Could be a PATS issue.

 

could be a hood switch, won't start if it thinks the hood is open
could be a brake switch, won't start if it thinks the brake is pressed
could be a problem with the pats bypass module