Been doing much, much reading regarding the infamous cold start issues.

I need some more brain power on this issue.

Rundown:

When ambient temp is above 0 celcius, no problems. As the ambient temp drops to -5 celcius and below, issues arise.

Truck starts just fine. GPR is good as there is good draw, no 'romp romp'.

BUT . . .

As the truck idles for a bit, it starts to act like its starving for fuel until it knocks, romps, and dies.

Trying to restart it right away is a no go.

Let it sit for a bit, meaning a couple hours. Turn the ignition key, let the fuel pump cycle, count to 40 seconds in total, truck start and idles fine.

Then this again, as the truck idles for a bit, it starts to act like its starving for fuel until it knocks, romps, and dies.

Yet when it warms up, I can drive no problem. Huh?

I have done the following:

Added proper additive to fuel for cold weather
Changed fuel filter
Changed all 8 glow plugs
Test GPR, passed
Checked UVCH and applied shim fix, all good

So . . . . .

All I am really left with is what, fuel pump? Could it be that the fuel pump is weak enough that when it gets colder out, it can flow enough fuel to keep the bowl full, hence the gradual 'starving' of fuel symptom?

Seriously: and

 

Have you done the in tank mods? With your issue being cold related, I'd be checking fuel pressure to see if that's dropping off. Maybe even drain some fuel out of the fuel bowl into a clear bottle and leave it out overnight so you can look at it during the colder temps.

Maybe it is gelling a little and some partially clogged screens make it worse.

 

I haven't done the in tank mods. I hear you about the possible gelling issue, but I have added proper additives to help combat this, I too thought the same thing. However, you raise a good point about possible partialy clogged screens and gelling fuel.

 

With these symptoms I say it is starving for fuel. They knock like crazy as they start to run out of fuel.