C h a z

Just had Zoe's Suzuki Alto MOT'd for the first time and it has failed on the Co2 emissions. What would be a common cause of something like this?

simb 2

iTrader: (3)

The 'cat' could be gone.

simb

dnb

CO2?

Could be the cat or the lambda sensor. Do you know what the measured lambda reading made on the test was? This could be a clue.

C h a z

Fast Idle Test
Co: <0.3% vol 0.69% vol
HC: <200 ppm vol 105 ppm vol
lambda: 0.970-1.030 1.012

Natural Idle Test
Co: <0.5 % Vol 0.83% vol

Lee uk300

Mabe the cat was not hot enough at the time of test.

Dark Blue Mark

Not normally the cat...

I have had 3 different Subaru's fail MOT's for this and its always been the O2 sensor.

Uses this off boost, which is the RMP the test takes place. If its failed / failing it will run rich and cause the high C0 reading.

Try a new one.

MB