Vehicle cut out on the road and was recovered to the workshop.
On cranking there was no common rail pressure on live data.
We found the fuel was a milky yellow colour (in fact a friend of mine pumped 25 litres out of a car he was selling and it was the same colour, but that was an old Citroen ZX so it probably didn't care). So it seems that we have a fuel contamination issue. I fitted a squeeze bulb between the filter and the pump and found that the engine will run if I keep plenty of pressure on the bulb. When I stop squeezing the engine will sometimes continue to run but usually stops as fuel rail pressure slowly decays. I will give the pump a temporary supply of clean fuel tomorrow. No evidence of metal particles in the filter by the way. In the meantime I am concerned that the tandem lift pump is failing would this be reasonable supposition?