hi folks, looking for some advice, just took my scoob for its annual check up and its failed emissions were thru the roof on c02 content 2.40!!! only mods are pipercross cone filter s/s exhuast and a scooby pro chip. could it be the chip that has done this or is it more likely to be lambda sensor

 

Try taking out the chip and see if she runs clean on the exhaust instead of black - its very basic test but might give you the answer - other than that you'd need to know your exhaust gas readings with a gauge. You can clean the backbox and take her for a decent run

As a side question, do you know what revs they did the test at?