Hello,

Had my car MOT'd today and it has failed on CO emissions. can anyone shed any light on why, before I start changing things.....

A6 2.4 auto 1998 (AGA Engine). No faults found using VAG-COM??

Fast idle Test
CO level = Fail 3.81% (pass 0.3%)
HC = pass 142ppm
Lambda = fail 0.90 (pass 0.97 - 1.03)

Second Fast idle
CO= 4.34% fail
HC= 185ppm pass
Lambda= 0.88 fail

Natural idle Test
CO= 5.35% Fail (pass 0.5%)


Any help on this would be gratefully appreciated

Cheers