nct exhaust emissions

bingou

hi everyone,
Just trying to get some information about this co emissions, I have passed my nct test today and everything was fine as the car is only 4 years old, anyway my lambda is 0.998, co 0.20% and HC 70 ppm.

It says here on the nct report that above CO 0.2% you fail. Now that does mean that I was very close to fail on this CO, should I check this or tune the engine or something? As the car is quite new, shouldn't this CO emissions be under that 0.2% rather than just in that limit.

Thanks.:)

meathstevie

Worry about it in two years.

E92

bingou wrote: »

hi everyone,
Just trying to get some information about this co emissions, I have passed my nct test today and everything was fine as the car is only 4 years old, anyway my lambda is 0.998, co 0.20% and HC 70 ppm.

It says here on the nct report that above CO 0.2% you fail. Now that does mean that I was very close to fail on this CO, should I check this or tune the engine or something? As the car is quite new, shouldn't this CO emissions be under that 0.2% rather than just in that limit.

Thanks.:)

Has the engine diagnostic light come on?

Has it been driving differently recently?

If the answer to both of these is no then I wouldn't get too worried about it, you do need to give the car a good thrashing more often though, driving it too gently results in carbon emissions creaping up as carbon keeps building up in the engine if it's driven too gently because it doesn't get a chance to burn off properly. Oh and if you drive it in town or at low speeds then this often causes the emissions to creap up too.

Darragh29

bingou wrote: »

hi everyone,
Just trying to get some information about this co emissions, I have passed my nct test today and everything was fine as the car is only 4 years old, anyway my lambda is 0.998, co 0.20% and HC 70 ppm.

It says here on the nct report that above CO 0.2% you fail. Now that does mean that I was very close to fail on this CO, should I check this or tune the engine or something? As the car is quite new, shouldn't this CO emissions be under that 0.2% rather than just in that limit.

Thanks.:)

OP the CO upper limit is 0.3%. You could bring your car back tomorrow for the same test and you would get a result of 0.02%. The results depend to a large degree on engine temperature. If you look at CO test results done on a cold engine, they are off the scale, then as the engine warms up and the cat & lambda sensor reach their operating temperatures, the results fall back down to usually 0% or very close to 0%, all other things being equal..

This is why you should have the vehicle well warned up before going for the NCT. Loads of other factors can influence emissions data, too many to mention here, but just to name a few, spark plug condition, cat condition, engine manifold vacuum leaks, etc, etc... I wouldn't worry about it if I was you, if it passed, all is well...

bingou

thanks everyone!! I think you people are right, it probably needs a good thrashing on the motorway, some nice cruising at 60km/h on the m 50..... .

Thanks for your answers.!!

SV

bingou wrote: »

thanks everyone!! I think you people are right, it probably needs a good thrashing on the motorway, some nice cruising at 60km/h on the m 50..... .

Thanks for your answers.!!

I'd say it might need another 1 before that 60!