My 270cdi runs smoothly when I accelerate. That would be because the oxicate is full. Wouldn’t be too bad, it’s added. If this is the case, it just keeps running according to the secondary current principle. Dirty though, but otherwise without side effects. However, you can blow it free, so that it can fulfill its original task again. Best on a highway ride over 100km plus at 3000 turns. I have now gone to Brittany, felt about 400km with at least 3000Tours, rather more. But he’s at least the same as he did before driving. What else can I do, with the black clouds I’m really embarrassed. Despite retrofitted DPF. Can such a cat be defective too? Greetings Carsten