I have a early 2004 6.0 a few months ago it died on me going down the road. I had it towed to a diesel shop $3000.00 later it was the hpop while it was apart I had them do the injector o-rings, pipe seals, hpop, oil cooler, also replaced one injector. The problem now is that the other day I shut the truck off then got back in and it wouldn't start so I used a gas soaked rag over the intake tube and it started. What could be causing this after I had all these seals changed already that could cause an oil pressure issue with starting. Is there something I'm missing. The truck has an edge tuner set on stock since the repairs were done. It doesn't seem to be electrical to me since it starts when using the rag with gas and it stays running, it runs perfect after it starts no sluggish take offs or sputtering. just really confused at this point.

beating my head into a wall

 

My truck was doing the same exact thing minus it shutting off while driving. I have had it for two years now and if it gets to operating temp it will not turn back on for at least an hour maybe more. I am trying to find a how to on testing the high pressure oil system. I have had a new HPOP, stand pipes, dummy plugs, injector o-rings, and a branch tube installed and still will not hot start. I feel your pain.

 

mine doesn't shut off while driving since i had the hpop replaced just really frustrating after spending this much money expected it would stay running a lot longer with no problems

 

I hear ya on that one. I dropped $2700 into replacing a branch tube... was supposed to fix the issue. I thought I could trust the mechanic but I guess not... I am going to try and figure it out myself, it will be cheaper and if something doesn't afterward I know I screwed somthing up and I'm not out a crap ton of money. What I am guessing and from what I have heard is that it could be the smallest pin ***** in some random gasket somewhere in the high pressure oil system. Before my FICM started going out the truck would start like a champ after it sat all night. But if I drove it more than 15-20mins it absolutely will not start. I am going to try the gas on the rag method. I love the truck but this is just a nightmare.

 

mine starts and runs perfect after using the rag trick that's what has me confused

 

Do you have any type of tool that will read ICP pressure when you crank it? I have been using starting fluid which I know is not that great for the truck but it will force it to start when its hot. When I spray it the ICP still reads less that 500psi but it starts... so idk man. I'm no diesel mechanic either. So if you figure out what your issue is I will let you know what mine is.

 

I will definitely let you know

 

I have an '06 6.0 and was new to diesel engines when I bought it. I had the same problem
where it would start fine cold, but wouldn't start if the engine was warm. Not sure if this
will help you or not, but mine was unrelated to anything you've had done, it turned out
to be the glo-plug ignitor.... once that was replaced have never had another problem.
Hope you get it soon, so frustrating. I feel ya

 

Well I just pressure tested my HP oil system tonight. It was air tight not a single leak. I'm not quite sure where to go from here. I'm guessing Low Pressure Oil Pump or something completely unrelated to the HP system.

 

update: my truck has been in the shop for a week now the icp reads 600psi on crank the oil system is air tight they have been leaning towards the harness they did a tree test on Saturday trying to rule things out they are just as confused as me anybody else have luck yet