The ICP regulator was at 87% while cranking.

The position commanded was 87%, but the actual position could be anywhere. Yes, it could be the IPR sticking intermittently open. Without having a high pressure bench stand, you are pretty much stuck with replacing it if you think that is the source of the problem. There was a lot of work performed, it is possible a bit of contamination made it to the IPR valve before or after the repair.

Although highly unlikely in this case, wrong oil filter and cap?

 

It is very possible that contamination made it to the ipr before repairs. The truck had a roller lifter failure that wiped out the cam lobe and the low pressure oil pump gears.

It is also possible that the wrong oil filter and cap were installed. He payed me to change the oil 4000 miles ago and he used an autozone filter....not a motorcraft.

 

While I have never actually seen a 87%IPR I think you have a IPR problem or a very small
High pressure oil leak since you do eventually reach enough pressure to fire and run.

It could also be a low presure problem not being able to fill the resivoir fast enough altho I would lean toward the HP oil leak since even when running you only make 850 psi.

You would need further indepth testing to know for sure.

 

I changed the IPR to 50% at idle and the oil pressure went to 1500psi. I only did this for a split second because I didnt want to blow an oring or damage anything.

 

Is there anything else I can check or test? I hate changing parts without pinpointing what is wrong first.

 

That is where a tester IPR comes in handy. If you do enough 6.0 repairs it's worth having.

 

Any ideas what I should check? I honestly do not know where to start.

 

I guess I'll remove the driver's side valve cover tomorrow and look for a hpo leak. If it does have one it will probably be on the passenger side knowing my luck. There is a bit of a clearance issue between the valve cover and evaporator housing. I'll keep you posted.

 

First start of the day with the engine cold.....Took 7 seconds to start. I am definitely leaning toward a high pressure oil leak.

 

removed driver's side valve cover. It looks as though the oil is leaking from inbetween the oil rail and two of the injectors. Perhaps I am wrong about where the leak is. It was dark and hard to see with a flash light. I'll check again tomorrow in the daylight. Can you get just the seal on top of the injector or do you have to replace the whole injector?

 

I stumbled upon this after researching through google. Fuel Injector Top O-Rings/Seals ~ The Whole Story - Ford Truck Enthusiasts Forums
Thank God for google. This sound like exactly what happened. Now to do an air pressure test.

 

I guess from your previous posts that you missed the info on the nipple cup and top injector seal in other posts. Don't confuse the injector releasing pressurized oil as a top seal/nipple cup failure. As you read, as the nipple cup O-ring fails, it can slowly take out the top injector seal. Both of these are relatively new for repairs being available for over a year.

 

I am replacing all 8 nipple cup seals and all 8 injector seals.