So pulling my trailer and 4x4 and the truck dies without any other symptoms. No check engine light all other electrical remains working. This happened 6 times this trip always while pulling a grade but only after the truck has been running for a few hours. Each time, no warning and once the truck has set for 5 to 10 minutes it start up like normal. The longer i let it set the longer I can run before it does it again. ICP is 550ish at idle, 200ish while cranking. Check the FICM before the trip and it was at 47.5 to 48.5v key on engine off and running. STC, stand pipes, dummy plugs, ball cups have all been done.

Thoughts?

 

ICP should be 580 idle and more than 500 to start. You may have a failing pump or a leak in the HPO system.

Pull the ICP plug, that forces it to use default settings and drive/test under load. It will give a check engine light but won't hurt anything, clears when plugged back in. If it's failing still, pull the IPR and verify the screen isn't clogged, if not, I'd do an air test for leaks, no leak found.... HPOP. Are crank times long?

Have you done the STC fitting upgrade?

 

its a 2005.

STC was just done and the IPR screen was clean at that time. Less than 1500 miles ago.

Pulled the log and ICP is over 500 during crank and 580 at idle. IPR is at 85% during crank and 22-24% at idle.

The two events i have logged show the following.

First Event - Before it cut out. VSS 53, RPM 1985, ICP 2697, EOT 217, IPR 62.7% ECT 208 ECT 920
First Event - After it cut out VSS 53, RPM 1985, ICP 997, EOT 217, IPR 85%, ECT 208 ECT 920

Second Event - Before it cut out. VSS 44, RPM 2125, ICP 3094, EOT 218, IPR 75.6% ECT 210 ECT 929
Second Event - After it cut out VSS 44, RPM 2125, ICP 298, EOT 218, IPR 85% ECT 210 ECT 929

 

85% on the ICP is fully open. Second event after cut out is ICP 298, that's to low to run let alone start. A lot can change in 1500 miles, don't assume its fine until you rule it out. Its asking for more pressure, the ICP is open all the way and something isn't allowing pressure to build. Is the IPR screen clean?
Clogged screen, failing HPOP, clogged IPR valve or a HPO leak... your choices as far as I can see.

First event after cut out, pressure is 997 and the ICP is fully open... asking for more. You've got a leak, failed o-ring or something of that nature. Letting it sit allows the oil to cool, easier to build pressure with cold oil, thin oil needs more pressure because it's flowing easy. Your loosing pressure somewhere, air test it, check the screen or a stuck IPR valve.

Allowed to continue, you'll have a hot, no start until it cools down.

 

Same question here in this post; https://www.ford-trucks.com/forums/1...p-problem.html

check your oil filter cap?

 

Maybe a miss quote but you stated your ECT was over 900 for both events?

 

What year truck? also the ipr valve is t'd into the hpo system, the valves closes to produce a higher pressure. verify your oil isn't fuel diluted, usually this will show by the truck making oil on the stick. also verify your ipr screen is ok, not pushed in or ripped. make sure you are running a oem oil filter and cap. aftermarket parts do not close the drain back valve in the filter housing, dumping base oil pressure back to the pan. the dash gauge is one step above useless, it shows normal anytime above 7 psi. base oil supply problems will look like hpo problems in high demand situations.

 

I figured he meant EGT--I could be wrong though

 

So after watching Diesel Tech Ron videos and looking at my log it clicked that the ipr has a 200 lb spring in it and every time the truck dies it drops to 200 psi.

A little more digging and talking to a few techs i found out that the HPOP's in the 2005's usually do not fail and that they had seen IPR's fail when heat saturated and after a few minutes the truck starts right up.

So I changed the IPR, rearranged the finger on a manifold bolt, and problem solved.

Now i just need to figure out why my brake pedal needs to be applied to about half down before I have good braking. I've bled the system 3 times, wheel bearing are good, pumping doesn't help. Truck stops fine just the pedal seems low and soft.

 

Great job!
Hydro boost may be failing. The power steering pump goes to the steering and brakes, hows the steering acting?

 

steering seems fine. going to try to flush the hydro boost and bleed the abs since we just had the cab off and the abs module was moved around.