Car runs better only during DPF regen

[willg]

Mine is doing the exact same thing. Anyone has any updates on this?

Still unresolved for me

 

[willg]

Might have made some progress with this: The PCV pipe seal near the turbo inlet seemed a bit loose, so I've pushed it in as much as possible and made sure the inlet batwing sits snugly on the turbo inlet. I've ordered a replacement PCV which will come with an upgraded seal as per this thread as the car has just hit 60k so figure as preventative maintenance it's worth replacing the whole assembly. OM642 PCV Upgrade | Engine

Right now the car is running smoother and quieter - much more in line with my expectations. But it could all just coincide with the colder weather I'll report back once I've installed the upgraded PCV too.

 

[willg]

I replaced the PCV with the newer version so now the seal for the PCV near the turbo inlet is brand new. I also removed and reinstalled and tightened up the turbo inlet seal and jubilee clip.

I think I'm making progress, but it's hard to tell if it's just because it's more eager than before, so it's moving passed the vibration rev range quickly as it revs up faster, or whether the combustion process is better. I know sometimes adaptations take awhile after a change. Either way it's an improvement.

Having said that, it did another regen today and it was smoother still.

 

[willg]

So a few thousand miles later the car went into limp with an EGR fault. Mercedes fitted a new EGR valve and it has massively improved it - the car runs like it did only during regen - all the time. Smooth and responsive and without clatter.