53 plate iveco uni jet engine hsi turbo?

It seems that every iveco van has the same sort o problems my injector light keeps flashing on and off cuts out then starts when cooled down and does the jerk back and forth when picking up speed. SO could you please put these main problems in order for me to get done first leak off test for injectors or electric stop solenoid or fuel leak sensor or contacts in the injector plugs need closing up or a new loom fitted any help please many thanks Gary