[PeteChappers]

Phoned my volvo dealer and got put through to there mechanic's and in a word they dont think its worth me taking it to them as it will cost me around 500+ quid just to run the diagnostics potentially.

They did recommend a garage how ever, which is the garage im already using...

So iv been back in touch with them where they are going to have another look at it. I have explained that basically i cant understand why it would misfire when all the original fault was the DPF etc.

one thing the Volvo dealer said was he has never in all the years hes worked there seen a internal cam chain go out of sync. he did say check the ADM fluid? but when i mentioned that the original garage said they have checked it.

So im going to get a vida+dice and try to fix it my self, then get them to look at it after Christmas if it still doesnt work i will sadly scrap/part x... what ever...

I noticed some strange things yesterday playing around when i Increase the RPM from idle slow every thing is sweet untill the 3100rpm mark where it starts to misfire then when i start lowering the rpm back down again slowly its start misfiring ( but not as bad ) at the 1800rpm mark... go to idle and back up to 1800 its fine back up to 3100 where is misfires then back to 1800 it misfires again so on and so forth.

So i was wondering could it be a Turbo, mass air sensors or vacuum fault?
If i remove the mass air sensor should the engine stop or go in to limp?
I have already removed and cleaned the EGR valve which seems to be fine.
Some 1 had mentioned removing an injector putting it in a cup and turn the engine over and see if it squirts fuel in to the cup and work my way through all the injectors, will that work?
any other random thoughts or tips you could throw at me?

Thanks