CO2 massive MOT failure, what's wrong?

[Johnny C]

Hi.
My car failed the MOT today, c
CO2limit was 30, it read 180. Any idea why? Engine was cold but he rerun the test several times, so engine should have warmed up. It's probably low on oil, could that influence the results? Failing that, what's the most likely cause, lambda sensor fail?

Cheers

 

[Graham-S]

Its always best to take the car for a good run to get it hot before MOT. A good thrashing also if not been used for a while then should pass

Good luck

Graham

 

[pse_SC]

They can’t do it reliably when it’s just warm ... needs to be reasonably up to proper temperature as Graham says []A diagnostic may show a little more...

 

[RHT45]

AFAIK the test is meant to be done with the engine fully up to to operating temperature, presumably for exactly this reason. I'd be asking to have it retested and at no charge. I had a similar thing, albeit with the GT3, so water cooled, when it came out of cold storage last September. It failed the MOT the morning after it had been driven from Herts to Stansted then on to Norwich, so definitely up to temperature for several hours but all on dual carriageway/motorway. However my mistake was not to give it a good doing in the gears before taking it for the test. End result was a fail and then a large bill at Autowerke (who were very good BTW) to get the reading down by changing sensor(s). Away from home so i don't have the bill to hand but from memory it wasn't the lambda sensor. Good luck.

 

[John Maddox]

How old was the fuel in it and what quality. When were the plugs changed and is the air filter dirty. Fill it with shell nitro and drive the long way to the mot station. Best of luck.