I believe its more about a safety issue with common rail, if an injector was to stick open there would be no control of engine revs going into orbit as the rail is under constant pressure. I think the manufacturers are sh!!!!ng themselves in case it causes a major accident. I have just bought the Delphi common rail tester and the conditions you are supposed to work in as to prevent dirt ingress is unbelievable. The video shows an immaculate workshop which is just a pre inspection area before being taken into a clean room with extraction equipment. I don't suppose even the biggest franchised dealers have these facilities, so I don't know who is supposed to repair them?.