Just had MOT done and it failed with high co2 readings and high lambda readings which confuses me as that contradicts each other?
Fast Idle Test:
CO2 - Max 0.20% - 0.63% Fail
HC - Max 200ppm - 60ppm Pass
Lambda - 0.97/1.03 - 1.06 Fail
Second Fast Idle Test:
CO2 - Max 0.20% - 0.24% Fail
HC - Max 200ppm - 52ppm Pass
Lambda - 0.97/1.03 - 1.04 Fail
Natural Idle Test:
CO2 - Max 0.20% - 0.16% Pass
Had a mechanic plug in a computer and he said one bank is under fueling and the other bank is over fueling.
If anyone has any ideas what it could be or could point me in the right directon of what could be the issue would help?
2007 350Z VQ35HR. Previous owner fitted Cobra Exhust and had an engine tune by 30hp.