Symptoms:
Truck cranks but no smoke.
Batteries are good, oil is topped off, motor cranks decent (not fast but not slow), and starter is tightly mounted.
No rpms on tach but already changed CPS out. WTS light works.
Buzz test works
Torque Pro says I'm getting 180rpms but not sure why so low- sounds faster than that.
With ICP plugged in, I'm getting 0 IPC and 25% IPR
With ICP unplugged, I'm getting 1450psi for IPC and 25% for IPR.
All readings fluctuate when cranking but not too bad.

What do you recommend for next steps?

 

Any leaks from HPOP or high pressure hoses?

With ICP sensor plugged in, does IPR duty cycle rise beyond 25% as you crank?

 

What is the truck voltage whole cranking? If it is under 10.5 it will not start.

Have you verified that the IPR is plugged in and the nut is tight on the back of it?

 

Motorcraft CPS?

 

 

And plug it in....whether you think it needs it or not. And Google 7.3 no-start flow chart and go from the top.

 

 

Umm, No one mentioned unplugging the CPS pirate , just the ICP. When you unplug the ICP the PCM will default to a given assumed value and if the truck starts when it would not before you know that you have a faulty ICP.


OP, what does your FIPW read when cranking? Voltage?

 

Thanks for the suggestions so far- I forgot to mention earlier that I already changed the IPR when I mis-diagnosed it as a bad IPR. Both the IPR and CPS are new Motorcraft and I have a new Motorcraft IPC but haven't put it on yet as it should fire with a bad IPC unplugged as stated earlier.

Updates since yesterday:
-Put on the battery charger overnight as suggested. Sits with 13V and cranks while holding 10.5V on the Torque Pro app. Probably not a battery issue...
-Plugged in the block heater this morning (it was only 55 deg last night here in Austin so seriously doubt it's a GPR/GP issue. GP's were also replaced 70k miles ago with new single shot sticks with new under valve cover wire harnesses). Water pump felt lukewarm so I know the heater was working
-FPIW is not reading while cranking so don't know if there is no signal or if I have wrong PID input. Verify this is the right PID for me:
FPIW PID ID: 221410, 6/0 max/min values, scale factor x1, ms unit type, ((A*256)+B)*.008 is the equation

On side note, I thought the buzz test generally indicates a good PCM/IDM (are these the same or difference computers?).

Batteries still on charger while waiting for more feedback.

 

Did you check out the flow chart and go from there?

 

Pcm tucked next to ebrake, idm stuffed inside d/s fender

 

 

My PID shows *8 otherwise the same as yours.
Have you checked the oil level in the HPOP reservoir? Not while cranking

 

I'm looking at the flowchart (thanks for reminding me) and I'm trying to figure out how to test the fuel pressure? I ruled it out early as the fuel bowl is full with a clean filter plus the frame boost pump kicks on for a few seconds when I turn the key on. I assumed the pressure is good but really should verify with a reading. I don't see a schrader valve or such like my old '95 PSD did. Where/how do I verify fuel pressure?

 

Fuel pressure is checked by removing one of 2 test ports on the back of the fuel bowl, Allen head plugs, DS is pre filter pressure, the PS side one is post filter pressure and impossible to hook up a sensor without removing the bowl, but its more valuable of a info point too