I have a 2002 F150 5.4L (VIN-L) that has been sitting in the driveway since February. I have been a mechanic for 30 years for large commercial trucks, and my own truck has me stumped. I'm sure I've forgotten something but I'll try to list everything I have tried so far. It started with crank no start, no check engine light, checked for trouble codes got a trouble code for the CHT(cylinder head temperature) sensor.

Replaced the CHT sensor. Cleared codes.

Dash lights up fine, shows mileage, and anti-theft is not flashing while cranking.

Fuel Pump does not seem make any sounds. Hit the tank with a hammer. Nothing.

A little fuel comes out of the schrader valve on the fuel rail when I push on it. I have not checked it with a pressure gauge.

Attempted to start with ether, nothing, so I'm assuming no spark.

Fuel pump inertia switch isn't triggered.

Checked several ground connections to the frame and checked ground connections in the PCM harness. All have less than 5 ohm resistance.

Unplugged and plugged back in cam shaft sensor.

Checked voltage on the TPS(throttle position sensor) I'm unsure about the results, if the TPS was bad wouldn't it just idle funny and/or stall?

Fuel Pump and PCM relays in the underhood fuse block appear to be good. All other fuses and relays appear to be good. I have been swapping the relays with one I think is good, although. Searched all over for additional relays, and found 3 inside the cab behind the passenger air-bag. Can't seem to find anything in the Haynes/Chilton manual that lists what they do. They are about half the size of the fuel pump relay.

Manually grounded the fuel pump relay, relay clicks but I don't hear a buzz from the fuel pump. Id like to run 12V to the fuel pump directly to see if that's my issue, but I'm not sure where to connect it without frying something important.

I bought the alldata.com DIY guide for my truck and it hasn't helped much. I have read extensively about others with similar problems and I just don't know what to do next.

My main question here is, if the fuel pump is bad, would that stop the spark plugs from working? I'd rather not replace the fuel pump without being absolutely sure.

 

These are the exact symptoms that I had when the fuel pump quit on my Mustang. Cranks but no start. Would not start even with starting fluid. I could find no documentation anywhere why there would not be spark if the fuel pump failed to make pressure, but it works that way. I would put a fuel pressure gauge on it just to be sure but it sounds like you have narrowed it down pretty well.

 

Check the following fuses: Central Junction Box-- Fuse 30-30amp.
Power Distribution Box-- Fuse 10-20amp. Battery Junction Box-- Fuse 18-15amp and Fuse 2-30amp.

The PCM relay supplies power to the Fuel Pump pull-in.

CJB Fuse30-30amp supplies power to the coil pacs as well as power to the pcm power diode and then to the pcm relay pull-in. So the fuel pump won't affect the spark but the pcm relay can keep the fuel pump from working.

 

The main hint you give, if accurate, is the Crank sensor is not outputting a signal to the PCM for spark and reference. The PCM must have this signal to time the coil drivers from the Crank sensor reference off the crank toothed wheel.
Are you sure the pump does not run at key turn on for at least 1 second?
If yes, the PCM is powered up.
If no, is the PCM power relay coming up to power the PCM?
Do the coils and injectors have 12 volt power standing on them?
Check these items out and get back.
Good luck.