[Hydro]

The IPR valve could be too tight, they only need to be 15-20 foot pounds -- too tight distorts the valve sleeve at the threads, and will bind up the internal poppet. Seen this many times in my line of work. Heat expanding the metals can cause the valve to work fine at lower temperatures and bind when hot.

Just one theory, but since you said it was in there tight, that may be the exact problem

 

[Hydro]

Interesting, ...thing is tho, if ICP pressure is fluctuating -- sensor voltage also has to fluctuate
the pressure reading is directly from the voltage -- unless it is switching to an inferred number

Possible your IPR is hanging a little bit?
you could screw the top part off and clean the armature of the fine metal particles -- also lets you access the tiny pintle valve (dont drop it)
my thread on the IPR tear down may help with details

 

[Hydro]

So, then PCM commanded more oil pressure, but the ICP only reported a 0.1 increase -- the change from 22 to 34 should have been more than that
would be good to know the ICP "desired" PID

Possibly the #8 injector is sticking part time? and causing the higher IPR value to be used to compensate?
is the fuel pressure good?

 

[Hydro]

Sounds like one of those "lope" tunes -- not sure what the tuners do to make the engine run line that, but may be a clue as to what to look for

Would have been a good time to use ForScan to change the value of the IPR and see if that affected the engine
Did the engine start like that? or had it idled long enough to go into high idle mode?

 

[Hydro]

Could just use ForScan to disable a cylinder, or disconnect a injector harness plug -- to test the theory

 

[Hydro]

Good, good, ...both of those will do the job
I would also command the IPR to see how the engine responds to the variations
about 480 psi, my engine will fail -- and the injectors get pretty noisy as the pressure goes higher -- but the engine still runs smooth

 

[Hydro]

when you do the cylinder cutout -- look at for each cylinder
RPM
IPR
ICP
Fuel pulse width
Load
Misfire - I forget what it is called

 

[Hydro]

The differences in the readings will be subtle
I would suggest copying them down and adding to a graph (spreadsheet) so you can easily spot the variations

Could easily be a chaffed harness, I would think a code tho
or loose connector on an injector or the ficm --
you would need to look inside the female terminal at the small spring leafs on the affected injector

I always kept spare terminals in my tool box, to use as a trial fit in the female terminals
that made it easy to spot a loose fitting terminal

 

[Hydro]

One quick thing I see from your chart -- then I am heading to sleep
the ICP voltage and pressure do not correspond always
the voltage may be using some hidden decimals, not sure
cyl 7 - 0.85 volts - 586.68 psi
cyl 5 - 0.86 volts - 576.15 psi

unless you mis-copied the numbers?

 

[Hydro]

Yeah, just wipe the cup out and run a drill bit thru the hole to get the carbon from where the tip goes
wrap some tape around the bit, so you dont drop it

A thin flat blade screw driver work well to scrape any stuck carbon, just be careful not to scratch
only really needs to be clean where the copper washer sits

Oil or Vaseline the orings just before installing -- they are silicone based so oil will make them swell some -- so lube just before
EDIT: I generally use chain saw bar oil from Tractor Supply for all assembly -- sticky non detergent oil

 

[Hydro]

The "blue towels" are fine

 

[Hydro]

Set of pull scales and a vice will check the calibration -- 12" for the little wrenches and 24" for the larger tools
will get you in the ball park for calibration

 

[Hydro]

Trick is getting tool that is "accurate" across the range -- would be interesting in seeing the chart of a 20 - 250 ft lb torque wrench
LoL, I'm sure somewhere in the range it would be dead on

-- or whatever is the common range of the HF tools

 

[Hydro]

@jokester00 as I like to say I'll make more money tomorrow

Sent from my SM-G973W using Tapatalk

Every time the tool truck rolls in the shop lot

 

[Hydro]

I posted these in another thread, but I use them a fair amount, so I thought I would add them here (there are a lot of other choices out there for similar tools):

Amazon.com: VIM Tools HCT1050 10-Piece Half-Cut Torx Driver Set : Tools & Home Improvement

Buy VIM Tools HCT1050 10-Piece Half-Cut Torx Driver Set: Screwdriver Bit Sets - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

VIM Tools HBR3 Double Ended 1/4" Hex Bit Ratchet

Buy Vim Products HBR3 Double Ended 1/4" Hex Bit Ratchet with an everday low price and fast shipping! JB Tools

www.jbtools.com

Amazon.com: Vim ToolsHBR5 Ratchet : Tools & Home Improvement

Buy Vim ToolsHBR5 Ratchet: Socket Wrenches - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

VIM Tools 8 in HEX BIT Ratchet (Vim-HBR8) - - Amazon.com

VIM Tools 8 in HEX BIT Ratchet (Vim-HBR8) - - Amazon.com

www.amazon.com

Williams also sells the little ratchet -- they make a lot of the tools for snap-on

Amazon.com

 

[Hydro]

A crack in the case really should not hurt the relay, unless water got in and corroded the contacts
Pop the cover off and look inside

 

[Hydro]

@Tathag Your truck running like this one ?

E450TN posted this vid showing how his truck was running -- worked out the be the IPR valve
Vid Here
Thread Here

 

[Hydro]

@jokester00 sounds to me like there is an induced ground to your IPR, causing it to randomly close and raise the pressure

A shorted wire inside the harness is a likely culprit -- that heat plays havoc on the insulation as @Tathag mentioned

 

[Hydro]

Thing is the IPR circuit will not throw a code, that I am aware of -- you may have a ground side problem, with a shorting wire -- hot side is fused, but with an intermittent it may not blow the fuse but still affect the solenoid position -- disconnecting the ICP still leaves the IPR problem active -- watching the ICP when the problem may show a erratic rise in pressure (voltage)

Would be great to have a separate PWM box to totally eliminate the PCM for a while as a test -- would not be difficult to build, I just don't have the time right now with Fall Farm chores -- 400 MHz , 12 volt PWM

 

[Hydro]

All fixed, ...just leave the laptop connected each time you drive