Right lads here is the result.

I took some advise from my local diesel specialists, that was take the injectors out and lets have a look, so i did, they were all knackered,and there was metal filings in them, you know where i'm going yep the whole system is shot

Metal filings everywhere, don't know why i didn't think of that before. The upshot of it is the vehicle is a financial write off, and according to the specialists these engines suffer from this problem, a shame, but there we go.

Thank you for your thoughts, and i hope that this helps one of you in the future