Have a 2015 6.7, was driving one day and it suddenly died and cranked slow and harsh like it was hydrolocked when i got it pulled over off the road. Checked the oil, level was pretty high and smelled like fuel. Towed it to buddies garage where we pulled the pressure control valve out of the fuel rail thinking it was a cp4 issue, it had very very minute shavings on it, nothing major. The fuel filter in front of the tank didnt appear to have and shiny metal shavings in it. I pulled all 8 glow plugs, all were bone dry, with them out i tried to crank it over and it still struggles. Batteries are brand new. I should add that i connected a snap on solus ultra scanner and got codes for cylinders 2, 4 and 6 injector balance/contribution. But like i said even after pulling the glow plugs it still struggles to crank. Any ideas? Spun bearing? Where would fuel be entering the crank case?
truck was recently tuned and deleted with ez lynk and has a gdp stock tune. Other than that is stock. 279k miles.

 

Well, I'd stop cranking it to begin with. Were the only codes for cylinder contribution?
Was there any smoke or odor during any of this as well?

A "tune and delete" is pretty big change and since it was a recent change, I'd start there. Who provided the tune and are you sure it's good?

 

metal even if its just dust is a bad sign.

 

That's the 1st thought I had when reading the post.

 

as in being cp4 related? How bad could the contamination be if theres nothing in the filter? And what would be causing it to struggle to crank

 

That you can see with the naked eye, perhaps. If you've got metal particles in the CP4 that you can see, then what is too small to see has already started accumulating in your injectors. It's possible that you initially experienced foreign contamination (water perhaps, or unreliable fuel) that caused the CP4 to begin self-destruction (and you caught it before it totally detonated and dumped noticeable particles in the return to the tank, yet to get picked up by the filter there - or maybe already happened just not picked up by the filter yet).

My uneducated guess is that those injector codes you're seeing indicate damaged injectors, and if it were me I'd be checking those immediately, especially given that you're seeing metal in the CP4. If they've been contaminated with metal, then it's game over, time to replace the whole shooting match. Only instead of replacing the CP4 with the same pump I'd recommend the S&S DCR.

Let us know what you discover. But, yeah, I would discontinue trying to get it started (as previously mentioned) until sussing the rest of the fuel system...

Edit: One other factor to consider - your CP4 has to be the earlier version, that doesn't have the pinned buckets (later 2020+ CP4.2 models rectified that design flaw). It's possible with the amount of mileage on your CP4 that it was worn to the point where the buckets could've started wandering on the cam lobe and contributed to the metal particles you're seeing, and you potentially caught it before it totally destructed. The only way to know for sure is to disassemble it. But, if you're going to go as far as removing it to do so, then it's not worth the effort; just replace it with the DCR. However, doesn't negate the need to check out the downstream contamination...

The fuel in the oil issue is troubling, in retrospect. You should probably drain some oil and inspect it from that perspective as well. Any brass found there and it's very bad news indeed...

 

i understand everything youve stated, any idea what would be causing the struggle to crank? It doesnt seem like any of the fuel related issues with the cp4 going out would cause that. Unless the fuel in the oil washed a crank or rod bearing?

 

That's why the final suggestion I made was to drain some oil and take a look at it. If it looks anywhere near suspicious then go from there. If excessive fuel effectively turned the oil into a solvent, then yeah, that's not good at all...

Also, are you able to turn over the crank by hand easily, with normal effort (no locking up or binding)?

I take it you've tested starter circuitry, battery loads, cables, etc.

 

Going off what Joe is saying, get a oil sample and send it off for analysis.

 

Drain and inspect the oil before going any further. If there is metal in the oil, well, time for a new motor.