Hi Steve have you a fax no as i have some info on these beasts that i will dig out !.One of the most common problems is injector loom and oil pressure switch that sits in the oil common rail as well as the IMV valve .These engines are an absolute money gobbler ring the dealers to see if has had its modified injectors seals turbo pick up pipes etc the list is endless. the injectors are operated by oil under very high pressure nearly 5000psi !! it may be worth removing the imv valve from the rear of high pressure pump and check the end for dirt stuck in valve but the dealers will just throw money at these untill they run so be warned !!
Regards John