CAT C15 /6NZ trouble continues

I'm only one hour from the Buffalo and Niagara border. If you've ever run into Ontario ( Canada) I'm between Niagara falls and Toronto.
My disposition is this; I get VERY ticked off at dishonesty, lack of integrity and I'm all about ethics. But I also know those are just word's and I realize you all don't know me from Adam..as dad always paraphrased.
Can't thank you all enough for your help and ongoing support.
Yesterday the truck ran excellent as was expected after it sat all weekend and was started a few times, a very common thing, which I just can't seem to get my head around.
Today wasn't ridiculously bad. Yes it stumbled etc but not violently.
Tomorrow I plan on trying to simulate a weekend, as I will start it, 2 minutes thereafter shut it down, wait 10 minutes and start it again, wait 5 minutes and shut it down. See what happens after that.
If it runs bad I was going to disconnect all power cables from batteries , wait 5 minutes and reconnect them, which I believe may / may not effect the ECM if in fact that's what is the cause.
Nothing to lose by trying to isolate this way...
Great thanks guys.
I'm starting my treck home now.
Be home 45 minutes or so and will check to see if anyone has any ideas or input re these methods for tomorrow.
All the best...

 

A bit of info.
Head was removed / rebuilt by CAT few weeks ago. Had a minor gasket leak at the common spot, rear drivers side.
Seeing as I've had the unresolved issue which CAT is stumped by also ( I can't recall but I'm guessing 14 times they tried to resolve it) they went deeper than simply head gasket / shim gasket they called it, and the shop foreman was actually from another CAT location, filling in. He I must say put some effort into it, sending the head out for tear down and rebuild . The CAT machine shop did find sticking exhaust valve on, I believe, #4 and #6, so they fixed it up and when I heard that I jumped for joy thinking that's it, all will be behind me.
But no such thing. That's my luck.
2 cylinder packs and bottom end bearings were done ( seeing as all 6 piston were pulled out )
Scores on liners in 2 holes is why the packs.
I wasn't overly excited when 10w 30 oil was put in when done. I drained it at 5,000 miles and a sample went to CAT.
For the 1st time I didn't get a clean bill of health on the oil analysis. " COPPER" was high but zero other wear metals present. CAT said in the report that
" COPPER being high could simply be a result of reaction between the oil and other metals, including copper"
I put my regular " Delo " 15/40 back in.
I'll send one more sample in 2 weeks before my warranty expires, FEB 19th this year, a few weeks from now.
But getting back to " tools etc" being left in engine, yes? Anything is possible, but I would hope that if a foreign body was left inside the engine journal's, it would have been caught in the above process.
I found a injector set tool under my valve cover of this engine a year ago after cat replaced 2 injectors.
For a week I heard a tin type rattle with engine idling . I pulled the cover a there it was. I brought it back to CAT.
They laughed, nothing more.

 

In post #2, pushbroom posted a CAT wiring diagram for me. Showing ECM power and ground from battery .
I could swear spaurland posted a multiple diagram of all wiring, I checked post 8 but it's not there. I also went through all 28 pages but non to be found.
Did I overlook it ?
I'm working still but have an idea.
I'm told there is 3 such power supplies to the ECM, and I've double checked 2 which are directly from batteries but want to find the 3rd circuit which I'm told stems from ignition circuit, but exactly where the wire's ( positive and negative) physically connect to I'm still searching.
Any ideas appreciated

 

Thanks Pushbroom

Much appreciated
I've taken an hour already to review it.
I think it may take at least another hour and then some...
Your help with this wiring schematics will help me check various power sources and supply to the ECM and I'll check power to and from the TPS and others as well.
All day it ran especially bad.
I unloaded / dumped my last load of the day about 90 minutes ago, did some paperwork, had a look at the schematics you sent and headed home (45 minutes ride) and for who knows what reason, truck ran perfect all the way home.
Just wish I could figure out what made it change..all I did was idle 90 minutes and turn the heat off ( 18 cold degrees here but I haven't felt well lately so turned heat off...that's it that's all)
Did colder cab air shrink a wire in behind the dashboard....1 mm ?
Where why how...
What a challenge..
Have a good night.
Thanks again