High CO2 emissions

[manity]

Hi all could anyone help with an emissions question..

i have a 2004 1.4 polo it recently failed its MOT ( natural idle CO2 = 0.40 pass .... second idle CO2 = 0.42 fail and fast idle CO2 0.44 fail).

i changed the air filter and plugs added some injector cleaner and took it for a 20 mile run in 3 ( automatic). its wifes car and only does around town driving about 10 miles a day max so expected it was a bit clogged up.

as a result 2nd MOT reading were a close pass ( natural idle CO2 = 0.32 pass ... second idle CO2 = 0.30 pass and fast idle CO2 0.34 fail).

i have checked there are no fault codes and although it passed just. the readings still seem high ( what should they be? average).

ive included a screen shot of MOT results as a pic.

any help would be great thanks.


35831

[34stuey]

Hi,

just had the same problem this week. Given your description it sounds like the Catalytic converter (Cat) isn’t working and likely due to the short journeys which results in the Cat not reaching temperature sufficiently to prevent a film forming over the active precious metal coating. So the solution which worked for me is to use “Cataclean” additive to the fuel, petrol and diesel versions, available from most motor factors etc, do a search to find it.
Similar to your MOT failure the CO on my polo was 0.44 on both tests, so a fail, before using the cleaner, after the cleaner it dropped to 0.25 and Pass!
Give it a try if it’s doesn’t result in lower CO then the Cat is likely damaged beyond repair.

let me know how you get on.

[Crasher]

It isn’t Co2... Carbon Dioxide (AKA the elixir of life), it is Co or Carbon Monoxide, rather more deadly...