04 6.0L with a late 03 build date here. To make a long story short, hard start/no start when hot. My research has narrowed this down to an HPO leak. What can I change with regards to HPO seals and O-rings by just pulling the valve covers on this late 03 build date engine? And what is the most probable culprit for the leak? I have only been able to find posts which seem have info related to to this subject for the 05's and up. And I am pretty sure they are different with regards to the HPO system.

 

Check for a vapor lock problem before you tear in.

It can be both or just HPOP.. though HPOP is more likely.

 

Well I am pretty sure I have narrowed it down to a high pressure oil leak. I just need to try and find out the most likely source of high pressure oil leaks on this late 03 build 6.0L. And what seals I can change by just pulling the valve covers? or should I go all the uder the HPOP cover and change seals there too. Can the stand pipes be taken out and there seals be replaced by just pulling the valve covers?

 

You'll find the procedure for troubleshooting the High Pressure Oil System in this thread:

https://www.ford-trucks.com/forums/8...condition.html

 

https://www.ford-trucks.com/forums/1...l#post10463177

 

That has got to be the biggest load of horse hockey I've ever seen in my life. The fuel pump HAS to be able to lift fuel out of the tank even if the pump impellers are spinning in air (or vapor). If it couldn't do this, the pump could not prime itself after you changed the fuel filters, or if you happened to run out of fuel, or whatever. Given that the pump is self-priming and the fuel system is recirculating up to the upper fuel bowl, a "vapor lock" is highly improbable, if not just down right impossible.

 

I am pretty sure I have the problem diagnosed. Pretty sure it is a high pressure oil leak. Just need to know what I can change with regards to seals and stand pipes by just removing the valve covers and what other seals I can change by pulling the HPOP cover. And was wondering if anyone knew what the most common leaky component would be.

 

Not much in the way of seals that's replaceable. If you have air tested the system then you'll know where the air leak is. How about a quick run through on your diagnosis. Might save you a lot of time and money.

 

Well I have fairly new (3 months old) upgraded higher voltage FICM from Swamps Diesel. When my FICM was going out the truck would die while running then usually start back then die again shortly after. Local shop ran their Snap-on scanner on it for me and determined that it was the FICM. I send my FICM to Swamps, they rebuilt it, I put it back in and problem fixed. Quick starts and it ran great with no dieing out. Had been running and starting perfect for 3 months

Well about a week ago I got home form work and shut the truck off for about 45 min then was gonna run to the grocery. Got in and cranked for about 10 sec and no start there were no other signs. The truck had been previously running and starting perfect. I did 4 or 5 more 10 to 15 second cycles and it finally started. Ran perfect with no problems starting for two more days. Then I got in it for lunch two days later (truck was still slightly warm from morning trip to work) and same thing. It finally started after 4 or 5 15 second cycles. Ran perfect and started perfect for at least 4 more days. Then I stopped at the post office with truck at normal running temp, turned it off for about 2 min max, ran in the post office, came out and no start at all even after sitting for over an hour. Had to get towed home. The truck sat in the driveway from 2pm to 8pm. I figured just for the hell of it I would give it a try after it has sat for 6 hours and it started instantly and ran perfect. I started it several times within 10 min or so and it started perfect every time. The next morning started it again and it started perfect. Then I turned it on high idle for 15 min or so to let it get to operating temp. Then I turned it off and it would not start. I let it sit until that night 10 hours or so and it started right up again. The next day I plugged in a Blue Point scanner which does KOEO and a KOER test and there were no codes at all. I had a fuel pressure gage hooked up to the truck the whole time it was in the drive way and there was always about 52 psi of fuel pressure even when the truck would not start. This is what leads me to believe it is a high pressure oil leak. Not sure of an easy way to test with air. Being that this is a late 03 build date the ICP sensor is in the backunder the turbo.

 

2003 model years are a ROYAL PITA to attempt an air test on. In my experience (as well as many other Ford techs), high pressure oil system no-starts have almost always ended up being caused by a failing high pressure oil pump. If you are at the point of having it disassembled down to the pump. You can actually air test it by removing the pump and cover completely. Use a rubber tipped air nozzle that you can insert directly into the branch tube itself to see if there are air leaks present. Doing the "air test" by this method removes the high pressure oil pump and IPR valve out of the equation (as well as the discharge tube from the high pressure oil pump outlet to the branch tube). If this "test" results in no air leaks, that leaves you with either the high pressure oil pump itself and/or the IPR valve as the cause of your issue, or the low pressure oil system supply to the high pressure oil system.

 

In other words, someone is feeding you a whole pile of cowchips.

 

So m-chan68? In your humble opinion, if the HPOP was going out, could it still cause the truck to start fine when cold and sometimes not start when hot and run perfect once running. I have not torn into the engine yet. Was just trying to get a little better idea before I started.

Thanks a bunch to all for input.

 

USUALLY, when it fails to start when the engine is warm, it points squarely to a high pressure oil system leak, somehwere in the high pressure oil system circuit. But on 2003 model year engines in particular, there aren't really many seals in that circuit. You have the discharge tube on top of the high pressure oil pump, as well as the standpipe o-rings on the bottom where they thread into the branch tube. You then have the quick release type couplers on the top end of the standpipe to the braided metal mesh supply lines to the high pressure oil rails. About the least instrusive test you can perform, if you must, is remove the driver side valve cover in order to gain access to the driver side oil rail. There is a very small threaded plug on top of the rail (don't ask me the thread size). If you can find yourself a fitting that will thread into this, that you can connect an air line to (with IPR Duty Cycle commanded to 100%), that will be the easiest way you can perform the same air test of the system that is done with later model year versions.

But to completely honest, high pressure pressure pump or IPR valve failures usually cause a no-start PERIOD symptom (due to insufficient ICP pressure).

 

pretty much EXACTLY what he said.

 

Hey M chan68 what kind of women are at the shop these days