Cranks but will not start

Hello,

This sounds like a classic fuel pump issue but to be sure can you hear the pump run in the tank without cranking the engine over (key on) here is a guide that will help us get started.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Please run down these guides and report back.

Thanks, it ran fine all week and then did it again today. Then ran fine.
Since I already disabled the security system. I'll change the fuel pump next week and see what happens. It's over 100,000 miles anyway.

It could be a crankshaft sensor as well. here is a guide and diagrams below to show you on your truck. When this sensor goes out it will not leave a code.

https://www.2carpros.com/articles/crankshaft-angle-sensor-replacement

Check out the diagrams (below). Please let us know what happens.

Ken, So I have been working on this now for a while. I replaced both the Cam and Crank Sensors. Replaced the Fuel Pump and filler pipe while I was at it.
Ran fine for a few days then it just started running rough and then would go back to Cranking without starting.
Replaced the ECM--FS1 rebuilt Plug and play matched to the VIN numbers.
Still Hard Cranking before it starts and then wont Idle.
Replaced the Idle air control valve and the Throttle position Sensor
Same problems.
The Three codes I am getting are
PO320 (Power train Ignition? Distributor speed input Circuit ) P1281 ( Power Train) and a pending fault of P1698 ( Power train)

What am I missing or is it just time to haul it to a mechanic?

I have seen the ASD relay cause this issue which would be a cheap fix. the PCM could be going out as well. We should check the wiring from the sensors to the PCM. here is a guide to help with the engine wiring diagrams below:

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Please let us know what you find.

Automatic Shut Down Relay In power distribution center.