Recently bought a 03 CCSB Lariat 5.4 4x4. 214k miles. Long story short, go to start it up, crank no start every time. If you dont immediately try to start it and leave the key in the ignition in the RUN position for an extended amount of time and try and start it, it will start, sometimes if its not freezing cold out. When it's cold, I've had to leave the key in the run position for 15-20 minutes before I could get it to start. All of this with no CEL.

I have replaced the fuel pump, plugs, coil packs, crank sensor, and cam sensor. It is not a PATS issue as I don't have a rapidly flashing THEFT light when attempting to crank.

Once the truck cranks, it runs fine. It's got old raggedy glass packs that Im pretty sure are leaking but again no CEL.

Took to my local shop, they're saying PCM is bad. What are anyone's thoughts.

 

The cluster needs to communicate with the processor
Regardless of the theft light on / off, or blinking, if the com is lost, the truck won't start
A NGS and a bunch of PIDS to monitor what's happening is the ticket
I think if the shop replaces the processor, and programs it to your truck, you will still have the exact same issue
Fairly complicated problem and a NGS is what the dealer would plug in to it back in the day
This is what you want to find
They are out there cheap at times
Otherwise, I would hit the Ford dealer for a proper diagnosis