Fail nct on emissions

Fatchopsabbie

Hi everyone looking for some advice please
My 99c fiesta has just failed the nct for the 3rd time on emissions.
The readings arent sky high
The lambda is getting a pass but the co is 0.33%
It should not be above 0.30%
The last reading was 0.35%
I seem to have got it down a little by using diptane.
The tester was very helpful for a change and he suggested cleaning the sensor, diptane, and cleaning the airflow??
He said it wouldnt be the cat as the readings would be sky high??
Has anyone any suggestions please

Anjobe

You need to post up the full results, so that we can see the exact lambda values and the difference between the high idle and low idle readings.

I am guessing you failed for CO on the high idle only, in which case replacing the air filter could do it - when was the car last serviced?

Fatchopsabbie

Anjobe wrote: »

You need to post up the full results, so that we can see the exact lambda values and the difference between the high idle and low idle readings.

I am guessing you failed for CO on the high idle only, in which case replacing the air filter could do it - when was the car last serviced?

Hiya
On the low idle the results were co 0.32% at 890rpm
Hc was 188 ppm

On high idle at 3.240 rpm lambda was 1.01
Co was 0.33%
Hc 49 ppm

Stoolbend

It could well be the cat

Fatchopsabbie

Stoolbend wrote: »

It could well be the cat

Hi my dad fitted a new air filter and then brought it to a garage to be tested
It failed again
Mechanic said it was the cat as well
Time to say bye bye to betsy

Sam Kade

Fatchopsabbie wrote: »

Hi my dad fitted a new air filter and then brought it to a garage to be tested
It failed again
Mechanic said it was the cat as well
Time to say bye bye to betsy

Just get a secondhand cat from a breakers yard.

Lead

Mine failed 3 times and it was the cat. Had to get the Airbag light fixed too so it was €320 all in for an A4.