Hi everyone, my first post am really hoping for some help please. Basically, had my golf vr6 (96N) for about a year and have had very few problems with it, until about a month ago. First mot check on emissions it was at 12% Co!!!! It had only been running badly for about a week in which time I had changed the blue ECT sensor (genuine one) and it had a new lambda sensor a couple of months previous. After a bit of discussion with the garage, they had suggested a cat, an air mass sensor, a lambda sensor......yeah i'd replace all that if they're paying for it, and they hadn't done a diagnostic!