Hi all I would welcome your views on this. no 4 injector on my Hymer 2.8 tdi threw up a fault approx 6 months ago. My mechanic fitted a new injector and all seemed to be good for two weeks. Then trouble, it seemed to run on three cylinders. Fortunately it happened close to home so the mechanic was able to respond promptly. He seemed to play around with the connections on the number 4 injector and it did run then ok. Yesterday No. 4 injector fault reappeared, so with new injector fitted, I presume I can rule out a bad injector, anybody have any pointers as what the issue might be. My mechanic is very good but I suspect his experience on commercial engines might be limited.