Hi all!
I´ve had a intermittent problem with my truck since the week before christmas. It comes and goes, sometimes everyday sometimes its fine for weeks, driving me crazy.

Symptoms:
I can be driving along, and all of a sudden she doesnt react to the throttle while in Drive. If i put it in Neutral I can rev the engine, but with a "stumble" at approx 1500rpm.
If i rev it to 2-3000 rpm a couple of times (10-20) in Neutral the stumble goes away and she runs fine for the rest of the trip.

It only comes when the temperature is fluctuating around 0°C, not when its colder or warmer for longer periods.
She idles fine in Neutral, just had a 225000 km check-up and service done including changing fuel filter.
Had some issues about 6 months ago with lack of Power overall, turned out to be the vac hose from solenoid to turbo that was that was blocked and cracked. this is not similar to that problem, why i dont Think its a turbo issue.

First time it happened i had been driving for 10 minutes, and after cruising on idle for 100 meters she didnt react when i pressed the throttle, but as soon as i put her in Neutral i could rev it (with the mentioned stumble). After a bit of cursing and revving the engine started making clanking noises when i revved it, but nothing on idle. Got it to a garage, he listened to it, drained the fuel filter to get rid of any water, poured 1l of methanol in the tank and it was fine for 2 weeks.
The problems came back and when it was at another garage for the 22.5K service, they noted a small amount of water in the filter but nothing unusual. Ran fine going from the workshop (100km trip) but problems came back this morning.

any suggestions? fuel supply? EGR issues (proposed by the garage)? turbo? bad electrical connections (plugs)?

been looking through the forum but havent found any matching issues, closest was this fron @Alcanara
Hi Guys.... I think I have the dreaded exhaust re circulation Problem (3)

Cheers.

forgot:
It only happens before the engine is properly warm i.e during the first 10-15 minutes of driving