Hi guys. Looking for someone with knowledge in the engine department - preferably fueling. My MOT on the Paseo failed emissions as they are sky high. 0.6* on the CO2 and 452 on the HC. My tester seems to think it is running rich on fuel. Something not telling it to burn enough? Something not sensing the correct amount of air? I had a new exhaust fitted 2 weeks ago. It'd about 4 months old but i had to remove the decat exhaust. I put it in with a cone filter however upon failing, dug out my OE aairboz and brand new filter, but it's still failing on those above figures. I still have the old exhaust, and my tester seems to think maybe the oxygen sensor from the exhaust would help matters. So we will try that tomorrow. Is there any other items to check? Plugs and leads seem tightly in there, but maybe the plugs aren't the correct ones? The car has done 170k on the original engine and has full service history, and he doesn't think it's anything to do with the valve stem seals as it is more air related. Any help would be great. Cheers Sam