Yes, search "F150 Triton 5.4L Crank & no start" & take a wild guess how many hits you get? We have gone through usual steps, replaced a fuel filter (easiest & cheapest) still no go.
We are not getting any fault codes. We "suspect" it may be the FPDM as this is a common theme however we INTENTIONALLY unplugged the module & tried to start it, no start of course but no error codes triggers, nothing on the OBD2 scanner. Tried two different OBD2 apps to ensure it wasn't something restricting us to read the codes. We've cranked it over so many times we just keep the battery charger on it at all times, probably need a new starter by the time we figure this out. For sh*t & giggles we unplugged many sensors (O2, Camshaft position) and not one code is being generated on the PCM. When searching trouble shooting PCM, generally you cannot communicate with the PCM & the truck runs poorly. Well we CAN communicate with the PCM & the trucks doesn't start, so not confident the PCM is the issue. Fuel pressure seems fine, kind of stumped on where to look next but more so why we cannot even intentionally trigger a fault code.

 

background/context helps. How long have you had it. When was it last runnning? What was last thing done to it before this problem? Are there any other issues / problems ?

 

Not much of a background, a friends truck, (2008 F150 5.4L Triton), apparently ran fine until it "just died" side of road, they towed it to our location as they are from out of town & had to return to work. So it is parked in our driveway & we are just trying to see why it died & if we can get it going again. We've ensured the IFS was reset (maybe they hit a pot hole hard), we have good fuel pressure in the rails, we hear the fuel pump engage when we turn it on, strong smell of fuel after we start turning it over & flood the system by pressing our foot on the gas pedal so you'd think it would at least catch & run for a couple seconds or something. All that said, doing something as simple as unplugging the FPDM & trying to start it, you'd think we would at least get a FPDM Offline DTC?

 

Do you have a check engine light on when the key is on, but engine off?

 

what does good pressure at the rail mean?, how much psi?

Suggest removing intake tubing spray fuel directly in TB, see if it pops/fires? (You learn a lot about potential fuel and spark questions with that test)

 

Yes it is "lit" when ignition in the ON position. BOTH OBD2 apps report Check Engine Light as "off" though as far as reading the onboard PCM (& no thrown faults, confirmed / pending). That is the oddity, even when we intentionally disconnect a sensor or disconnect FPDM, certainly a coded event like P1233 (as an example) should register in the PCM right?

 

Kpa is 390'sh while turning over, about 56 psi which is well within spec.
Have not sprayed anything into the TB, that was kind of last resort.
I have been more fixated on why we cannot intentionally create a DTC fault.

 

ok, just saw that you’d been doing stuff re: checking for fuel while also trying to get it to fire (in which case that simple test tells you a lot of info, quickly).