Hi Paul, you're correct with the it likely being a VVT fault. I've attached a basic reference guide and link to a video showing the usual sticking section at the very end of the travel, which they only seem to use intermittently.
They suffer with electric lift pumps in the tank failing, but you say the pressure is consistent? Live data should give you a desired fuel pressure and actual fuel pressure.
Have you put a pressure gauge either side of the filter to see if there's a restriction? I wonder if the fuel is waxing in the colder temperatures.
With the last fault being a split air hose, I would expect a P0101 code, so I wonder if it has been re-mapped with a DPF delete, and you're suffering with a blocked exhaust.....
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on July 14, 2016, 7:28 am, in reply to "