ok I have an update.. So I have swapped the ICP. it wont start with it plugged in at all, when unplugged it runs like crap.. so I threw an IPR at it.. no change at all.. Zip.. so figureing that the hpop does have 733xxx and it went dry, just maybe something wore out as it was old.. I had a Adrenalin pump sent up and same exact issue..when cranking the oil pressure gauge in the cluster comes up as it always has.

Ive disconnected the c138? connector and pinned out the icp, No issues, at-least between the connectors.
Im really thinking Electronic after replacing what I have on the oil system..

could this be a cps? would a cps make it feel like its a 5cyl? it feels unbalanced.. what else works with ICP when connected to make it run?

 

also when it does run there is no pressure coming out of the oil fill, no smoke, so I think the compression is fine well 733xxx miles fine.
not thinking injectors because it wont run with ICP disconnected.. if everything was connected and it started and still ran like crap then I would think injectors. I have to get it to start as is has first IMO.

just picked up a ipc pigtail because seems like that people are replacing them..

 

Possibly either LPOP or LPOP pickup tube in the sump?

Do you know if you're LPOP is maintaining level in the Reservoir ahead of the HPOP? With the engine running, how steady is your HPOP pressure? With the engine NOT running, just remove the fill plug shown in the picture in my post above and shine a light down into the Reservoir to see if it's full.

I don't recall seeing anyone ever post up a problem with the pickup tube (except possible pluggage), but at 733,xxx miles, I have to assume that every original item is very tired right now.

 

Which is it?

 

which is what Mark? I dont understand your question..
Ill check the reservoir.

as far as the Mileage and being worn out, it runs or ran until the other day as good as the day I got it.. No signs of anything, I have had 15000 pulling hills recently with no complaints, no shakes, no electrical issues.. I know the 7.3 bible says to randomly replace things just because its old, I dont subscribe to that theory, not saying its wrong but ifs its not broken dont fix it. lol

 

I too, like Pete, may have not been clear enough above in post #6. Please accept my apology too. I am thinking it is electrical as well at this point. Yes, the CPS which is basically a Hall Effect Sensor, can cause the issues that you describe. I would swap the CPS in from the other engine. Also, you might want to check the wiring on CPS pigtail as well to see if there is chaffing on the wires anywhere....pulling back the loom included.

There is a relationship between the CPS, ICP, and IPR somewhere in the ground circuit from my experience. There are reference voltages for these sensors that someone may be able to provide. I am not home or I would get them for you.

 

In your first post you state that it won't run with the ICP connected but runs like crap with it disconnected, in your second post you state that it won't run with the ICP disconnected.

 

See post #21 first.

When you swapped out HPOP's, did you make sure that the HPOP shaft to gear bolt was torqued properly? That interface relies solely on the friction provided by the torque on the bolt against the gear. As you know, there is no keyway to prevent slippage.

Also, try unplugging the EBP sensor while trying to crank...just for S&G's in case there is a ground issue.

To dig deeper, we really need the data that FORScan would provide. Otherwise, it is all guess work.

 

I wouldn't rule out injector issues so quickly. Unplugging the ICP doesn't change how the injectors work, but it might change the amount of oil pressure they see. I'd still be pulling valve covers and watching how it they spit oil when you try to start, or when it does start with the ICP unplugged.

The ICP, IPR, CPS aren't going to make it feel like it's running on 5 cylinders. Time to figure out which 3 aren't doing their part.

 

I hope you get this resolved soon. Love that 700K+ miles was not the reason for the problem.