Hesistant acceleration pd170

[Copeyface]

So im having a bit of an issue at the moment, not to sure where to look.

If i decide to pin the accelerator a bit (pulling on a motorway slip road or such likes) the car pulls like a train but then sort of holds back goes again and does this through the rev range. 3rd gear is the main culprit sometimes 4th how ever if i dont pin it as such and build the revs a little slower it will happily sail through wihtout an issue.

Its an 07 PFL VRS Diesel PD170.

 

Been wondering if maybe giving the EGR a good clean could help, altho starting to wonder if maybe the injector seals to as a bit of reading online seems to point towards these.

 

Its a well looked after car serviced regulary.

 

Any help would be appreciated to give me an idea of where to start looking.

 

[SuperbTWM]

Could be a dodgy MAF sensor, try running the car without it plugged in and see how it compares.

[Guest]

Perhaps a clogged fuel filter failing to flow sufficient fuel at peak demand.

[Copeyface]

Yeh it's due a service in a few thousand miles so Al bring it forward and get the fuel filter swapped, and also try with the maf unplugged and report back. Thanks for the suggestions

[DataflowDesign]

Do you have VCDS and can you run a graph whilst it is happening so we can see requested boost versus delivered boost.  Can you check and make sure the arm that controls the turbo vanes moves freely.

[Copeyface]

11 hours ago, DataflowDesign said:

Do you have VCDS and can you run a graph whilst it is happening so we can see requested boost versus delivered boost.  Can you check and make sure the arm that controls the turbo vanes moves freely.

I've got a cable coming so once it's here I will get the data. Will also give that  check. I realise there's not a great to do without being able to check logs ect 

[J.R.]

Maybe I should ask on the VCDS part of the forum but as a novice VCDS user still finding his way around the options could someone explain roughly how you go about live logging parameters like this, in fact especially this one?

 

It looks to be a very powerfull diagnostic tool if only I could use a fraction of it, my last car was always plagued with this issue, I sort of know what was going on and when and could keep on top of it with oven cleaner enemas but to see the datalogging would have told me so much more, the new vehicle had an overboost code logged so the enemas may have to continue but I would love to see the exact state of play