A brief story, engine let go in the van so I got an exchange unit as was easiest option, fitted all ok new filters fuel included, bled the system then tried to start it splutters and chucked a load of smoke out but won't ever fire. I checked fault codes and it read rail pressure low, when I read the live data it's only showing 400-500psi which is no where near enough.

I've checked leak off on injectors and nothing comes out. I've checked the return and only a dribble is returning.

My guess is the pump, but I've no idea why it would go all of a sudden as was perfect before? Engine dropped a rod but was running fine.