Working on a stock 2000 F350 Manual trans that i just put a used motor in.. Cranks over fine and starts on fluid (yes i know its bad lol) Changed every sensor, Had all the injectors tested, replaced the Hpop lines and new Hpop. I've cranked and cranked the IPR % goes right to 65% after 3 complete rotations and doesn't try to start at all not even a little smoke from the exhaust.. I have 3 of the same trucks and have swapped IDM computer ect and nothing changes.. Checked power/ohm ect at pigtails of sensors and all where it should be..new valve covers, compression is around 380psi on all cylinders.. all new injector O-rings no black in the fuel filter no diesel in the coolent/oil.. oil level good in both crank case and HPOP resivor.. around 30psi lpop while cranking.. ICP shows zero at all time.. unplugged icp also.. I ordered a IPR tool so im gonna try that tomorrow (9-8-22) Fuel pressure good and i also changed the engine harness just to see,I'm at a loss I've been working on the 7.3 for 15 years and this one has me up at night lol

 

Moved to 7.3L PSD engine forum, where the 7.3L experts reside.

Good luck with your repairs!

 

Do you have a wait to start light?

You say it starts on ether, does it continue to run after that or just fire and die?

Whats the fuel pressure reading?

I believe ICP should go to 600 while cranking... Someone will be along shortly to help diag that IPR. Did you look at the tinnerman nut on the IPR?

 

It fires right up then dies, and yes the nut is tight it's all new lol and yea i have a light..

 

What scanner are you using? any codes to reference that might help us?

Where did you get the IPR? Should be motorcraft from a reputable source only. Do you have the old IPR to try? Check the resistance on the IPR coil - should be about 10 ohms.

 

Obviously the 0 psi ICP is an issue. Unplugging the ICP sensor pretty much eliminates sensor/wiring issues on the sense side.

IPR pigtail in good shape? Can the IPR (good or bad) keep ICP at zero with a good HPOP?

 

A Bad IPR can for sure keep the ICP at zero. An easy IPR test, while I say easy it's a bit messy if the IPR is good, you can take the ICP sensor out. And crank the motor over a little bit and see if oil shoots out. If no oil, you have a reason for not building oil pressure from the hpop whether it be a bad Ipr, a faulty Hpop or bad flow to the hpop. It's a very barbaric test but it can tell you a lot.

 

As I said in my last comment, since your IPR is reading 65%, but your ICP says zero PSI, I would remove the ICP sensor from the head and crank the motor over a little bit and see if you are getting oil. This is a very simple test and while it can make a mess it can tell you a lot. Throw some napkin over the hole and watch for oil from the cab you will definitely see if oil is shooting out.

Logically thinking about it the sensor says you have zero ICP, what did it read with the ICP unplugged? With the ICP unplugged it should default to factory starting pressure on the reading with the scan tool. So say around 600 PSI or whatever the case is with your truck, with the ICP unplugged you should be seeing that while cranking because it defaults to stock.

Also, I'm sure scince you've been working on them so long, you already know but, did you make sure the hpop drive gear was settled properly when you torqued it? Checking this wouldn't matter until after the other test of course to see if you're getting oil pressure to the oil rails or not.

Also, is your scan tool reading rpm when cranking? If so it most of the time says good cps.

 

Have you bled the system yet? I may have missed it somewhere, been a long day and I'm not firing on all cylinders, but the pumps can get air locked and will not move a drop until the hose to each head is loosened to let oil gravity from the reservoir through the pump and to the head. Even with a failed IPR you should show some ICP so either the ICP isn't reporting correctly or the pump isn't moving oil.

 

I used a snap-on scanner but had to return it so using the forscan app on my laptop and same readings.. IPR is motorcraft and I put it in my other running truck to make sure it was good and worked fine in the other motor.

 

I cranked it over with lines in a bottle until i had oil and i also removed the caps off the end of each head and cranked until there was oil.

 

This would/should have been violent, and messy.

 

Yes the gear is set and torqued right, when i unplug the icp it changes nothing and scanner says 700psi when cranking. I have removed the sensor,line and cap at the end of the head and oil comes out but the pressure coming out of the line is minimal i can hold my finger over it and stop it (Drivers side) and the passenger side it trickles out. Like i said the Hpop is new out of the box and i know it could be bad but it's had the original one in it,another from a running motor i had on the shelf and now this one i doubt 3 are bad lol.. ive tested every part in my other running motor to verify and all worked fine.. All motorcraft sensors,oil,filters ect.. Codes i get are the expected low psi blah blah.. I got my IPR tool today so im gonna dead head the pump and see what happens and also put air to it and see if i have an internal leak, Maybe an injector is stuck open 🤷‍♂️🤷‍♂️ Lol im at a loss at the moment

 

Haha right but i have a hand held trigger hooked up to the starter solenoid so i can crank it over while under the hood to hold the lines.. I've had a couple lines crack and oh yea big mess within seconds

 

Ok 3 separate pumps all misbehaving exactly the same. That should narrow us down to an obstruction on the suction side between the pump and reservoir, or the hoses plugged some how.