have the same trouble, changed injectors, filter and both pum ps, eventually took it to the dealer to plug it in to the computer.
this pointed to the crankshaft sensor which the mechanic looked at reg 02, and apparently iveco made some engines and put only one thrust washer in, this eventually wears out and the crank has too much end float and the flywheel sensor cant read it as it is too far away. the dealer will pay for half the parts if you leave it for them to repair!
george j
March 2008