97 F-150 Dead - What am I missing??
 

I started it up the other day and backed out of the drive, then put it in gear and it promptly died. It hasn't started since. Turns over normally but will not fire. Fuel pump sounds ok, inertia switch is not tripped, and I have fuel at the rails. Ignition coil tests ok, and I checked and had spark in the #1 plug. I replaced the cam position sensor thinking it might be faulty, but still nothing. Primed it through the intake and it fires until the fuel burns off, so I suspect it is a fuel issue rather than ignition. One area of possible concern is the voltage to the cam postition sensor is very low, but that may very well be normal. I presume this comes from the PCM. The way it died left me puzzled - never a miss, hesitation, or anything like that. What else - any thoughts...timing, crank sensor, PCM fault? Oh yeah, no codes or CE light at all. Thanks in advance!!

Unplug the MAF sensor and see if it starts if so replace it

You tested for fuel at the rail but do you have pressure? When was the last time you replaced the fuel filter? Try removing the vacuum source to the fuel pressure regulator. That will spike the pressure.

Regards

Jean Marc Chartier

Have to measure the fuel system PRESSURE. Should have 35-55 psi at prime.

I unplugged the MAF sensor and got the same result. Tested the fuel pressure at the Schrader valve and got 34 psi with the key on, and then 36 psi when cranking. Also removed vacuum from fuel pressure regulator, and maybe got to 37 psi when cranking. Fuel filter is not very old. Any more ideas? Thanks for all of the input so far!

Check for power at the injector harness. If there, use a noid light to see of the injectors are being fired.

Steve