Failed My M.o.t (Help)

[aygokid]

right, it was the aygos first m.o.t today, went to pick it up and he said its failed, i asked what on he sed its giving wayyyy too high emisions, ive had a performance backbox fitted but thats not the fault he sed, he sed it could be a sensor :S:S what do yu guys reckon ? stuck with no car now

[Raistlin]

Sorry to hear that on such a young car...

[C_U_Jimi]

right, it was the aygos first m.o.t today, went to pick it up and he said its failed, i asked what on he sed its giving wayyyy too high emisions, ive had a performance backbox fitted but thats not the fault he sed, he sed it could be a sensor :S:S what do yu guys reckon ? stuck with no car now

The MOT tester should have given you a fail sheet listing the reason for failure and the figures. Can you post these, they may help someone understand what sensor failed.

Just a thought, when did you last change your air filter? Could be a choked filter.

[Jan van de Wouw]

Choked filter sounds plausible, or a failed or failing O2-sensor, but that would

usually be noticed by the ECU I'd think and it would put on the Check Engine light...