Really hope you can help. After 4 years, suspension, brakes cam belt hoses etc done and only failed the MOT on emmissions. 0.57% with a target of under 0.30%.
Changed the Catalytic converter. Added cataclean, added premium fuel. Drove it hard for 30 minutes on way to test centre but failed retest with same levels. Does any body have experience of this. Are there sensors that might need changing. Exhaust smells very rich even when engine hot. Any ideas appreciated