5.5 1.9TDI intermittent juddering/shaking

[tonyhart]

Hi there
I have got a worsening problem where the car violently judders when accelerating. If I turn the car off and on again, sometimes the problem is cured for the whole journey, however far. It seems like a lack of fuel getting into the cylinders, and power is slightly affected.
Im not sure where to start with this.
Has anybody here got a clue?
Cheers