Hello community ! Maybe someone has a tip in which direction I should look. The problem is the following: The car did not pass the AU because of too high CO values. The AU was already a drama before, because the car took a long time to meet the values, but this time it was not possible – despite 2 attempts with long warm-up in between. The CO values behaved quite strangely: First the values went down quite normally, even to 0.09. According to the program d After that, the values increased exorbitantly again, up to approx. 3.5. As if there was something ‘saturating’. Has someone ever had such an unusual problem and a tip for me. I would be very grateful for that; I don’t know where to start looking. MfG -RFH Rover 827 Si / BJ: 1996 Honda Motor , PGM Fi Control 124 KW / 169 PS to 2: 2055 / to 3: 357