I currently have a customers ml 320 in my shop with 50k on it that cancels out # 2 injector after running for 30 seconds. I did the following things fuel pressure test , compression test , ignition system test ,replaced # 2 injector. It had pulse when i checked it. Little did i know that pulse whent away after 30 seconds. I called mercedes and talked to one of the guys in the shop and we went through everything he sugested that i put a air flow sensor on it so i did it didnt help. They actually told me if that dosent solve my problem they will take it back i was supprised to hear that. In any case does anyone have any sugestions? By the way the system i use is alldata and the only thing i found is that it is possible for the computer to cancle individual injectors if it detects a problem. Thanks for any help. If you can suggest a tech line i dont mind paying i just need to fix this thing.