Hi

Can anyone shed light how to get a catalytic converter certificate that my car failed it's expertise on for lack of.  Had to have the converter changed in the UK, old car so garage put a 'generic' part in rather than Audi.  Passes the emissions tests with no problems.  If can't find how to get a certificate have to change a perfectly functioning 3month old catalytic converter with a expensive Audi part Ahhh !