My 2001 F150 5.4L just one day decided not to start. It will crank all day. I have a code reader and no codes are shown. The Anti-theft light does blink if I sit in the truck with the key forward. I did try my spare key and it does the same thing. I have never had a problem with the truck since I have owned it at 20,000 miles. Is there a anti-theft problem and if so what can be done about it? Thanks in advance.

 

Check the fuel rail pressure,possibly a dead Fuel pump?

 

Press the gas pedal slightly and try to start it. If it starts, the IAC (Idle Air Control) is bad.

 

Your anti-theft system has triggered. You can crank it forever and it will never fire since the computer has shut down the fuel system.

See any one of the dozens of PATS threads for advice, it's always the same.

Steve