Hi, I'm new to this forum but would just like to inform everyone that cataclean is a brilliant product. I have had great results from using it every 3-4 months in my GS. However I have been told by a highly recommended garage that if a mechanical part is broken. Or in the case of catalytic converter being 'clogged' or blocked too much there is no product on this earth as far as i'm aware that could unblock it. However I have seen with my own eyes cataclean fix cars with similar circumstances to yours including my own. Chances are in my opinion is your catalytic converter is damaged to the point of no repair, and you easily get a cat delete and have to find a 'Friendly Mot Tester' or you need a new Cat. I am sure if you were to buy a new cat then cataclean could be used as more of a maintenance product like it says you can use it every 3-4 months