CAT C15 /6NZ trouble continues

Yes. Bulkhead / firewall contact pins checked. I added a 2nd length of seal
( the hood closes down on it. It slips over the metal body moulding under windshield above firewall)
Peterbilt engineers were not thinking with that one. The moulding ended just above the electrical contacts, perfect if you want rain / wash water running over those multi plugs below.
And ya, the saga continues...unfortunately .
I often think, with CAT being given a mandate by me to " just fix it and send me the bill, I want it over with "
I gave them the truck for 13 days and said if fixing it means I have to spend $10,000 , go for it. I even gave them a to the point detailed description of what it does, when , how etc and when it doesn't. I also noted I would happily pay $1000 to the tech, in cash, just for identifying the underlying cause.
.....no takers.
I figured this much. If I have to get another truck, merely putting a new wet line on it would put me $5,000 plus out of pocket . Plus lost time from work, etc.. etc..
Maybe I should have offered more $.
Then again, I shouldn't have to, but I need someone to focus on the problem and some tech's are only there for a paycheck, not because it's their passion or give a sh##.
Again this weekend I'm going to meter out the ECM, wiggling and jiggling as I go. And re check the tank vents, check again for foreign debris in tanks. And a few more checks.
When my right fuel tank was removed, split ( hydraulic oil in one side, fuel in the other) and re-installed, the suction and fuel return lines in the tank are now of course closer together. I often wonder if this wss my problem, but I eliminated that thought when I ran a totally separate line from inside the fill back of left tank , draped over drivers step and connected to the primary fuel filter housing ( which was also replaced)
But no . It made zero change.
Gotta be ECM programming.
I've called CAT head office yesterday asking for their ECM electronics specialist ( if one exists )
CAT emailed me back saying someone will be contacting me shortly..
Key word..." shortly"...nothing yet.
Any thoughts by anyone on anything which may help me, please please post it here, I will get back to you every day.
Thanks guy's...

 

Yes. That's what I was recently told.
The entire TPS assembly is a package deal . However, replacement of merely the sensor requires calibration.
I'm assuming when you say "APS" you actually were attempting to type TPS for Throttle position sensor.
I'm digging out from a violent storm that dropped upwards of 4 ft in some areas but we only got 26", but drifts taller than myself. Thereafter I'm off to focus yet again on my issue. A pot of coffee, coveralls on, I put truck in my shop 2am Saturday morning to avoid drowning in melting snow when I turn heat on ( and it's needed today, it's -19 below today, was -24 overnight.
I'll check this site regularly in the event someone needs a picture, has an idea etc..
Great thanks guys

 

I hear ya. I think under the same principals.
-saw it for sale
-drove it. Beat it up. Called CAT to confirm s/n for 3+ years warranty left.
" ALL OK"
-Seller left truck at local shop ( we are all in farm country here. Salt of the earth kind of people) which serviced truck for years.
-i called that shop. Asked for them to install wet line. Change engine oil, air, fuel filters, engine oil, levelling valve etc.
Pass. Side tank sent out to be split into two compartments. One for 80 gall hydraulic oil. The other, fuel.
From the day I picked up the truck it's been stumbling , but always disappears after 5+ seconds my foot is " off" the throttle, when I then can put foot to floor , climbing steep grade with 142,800 lbs and not a pop. Not a stumble.
Any time I'm on the highway with even the mildest of not even possible for a skateboarder to stay rolling, grade on road downwards, I can put foot to floor with not a hickup. Dead smooth.
Slight upwards grade and it's the opposite, popping, shaking, stumbling.
So bad that the highly torqued big nut on tail of tranny backed off.
And the rear tranny seal now leaks.
( tranny replaced 8 months before I bought truck. Then I had it pulled 3 months after I bought it. Then, about 9 months ago I had it COMPLETELY REPLACED. NEW CLUTCH, FLYWHEEL WAS CUT, INPUT SHAFT, THROW BEARING, AND LOTS MORE)
-Still....the issue is here.
After 11 hours or so driving, it nearly all goes away.
Start and shut off engine a couple times over the weekend , come Monday it runs good to even " GREAT".
WHY ?
FUEL ISSUE?
ECM MEMORY ISSUE?
No idea. But I know I can't go on like this.
And thank you all for your continued help

 

Thanks for your help.
No. He didn't have any such symptoms.
He and I cross paths now and again.
The shop he used ( after a 2 year absence from trucking he's back into it again and back at that same local truck shop) and I've been using since buying this disaster, the shop owner let me go through his computer, checking every little repair, service records etc..
Nothing related whatsoever.
The only thing that I can think of that he may not be very forthcoming about is if he used a bullydog or similar, which habitually leaves ghost data . So I'm told.
Every fuel up I check again and again for anything in fuel tanks. Never anything found. But an hour ago when scoping my tanks I found what initially resembled a oval fishing lure on the bottom. Not magnetic my son and I ended up finding it was plastic, hard plastic. I ended up sucking it out but it disintegrated in my pony pump but it's now out.
But I also ran a home made stratoflex fuel line from the filler neck to primary fuel filter, a year + ago with no change. So I don't expect a fix with this.