Yes I think your right , they were reconditioned at gap injectors Birmingham £500 , done a leak off test at tickover for 5 min and 3 of the injectors are giving 30 mls and the other 18 mls
In the older diesels you could crack the pipes I turn to identify a problem injector but if you do this with a common rail I doesn't work the same as pressure will be lost to all four
Will have to be sorted because the lumpy tickover will end up destroying the dm flywheel