I am left with exhaust emission!

Hi guys,

For the inspection, I exhausted the exhaust, did not switch to the vehicle, went with a different catalyst again, did not pass again, the man looked at the oxygen sensor, I went to look at it, but they measured the oxygen sensor to work, what else would it be working? They said the carbon is high in the emission if I change my catalyst again? Previously emission was not a problem, now they are causing a lot of trouble recording with the camera. No matter how much language I spilled while measuring the emission. The car 2000 model 206 Xs 235 thousand spark plugs were just changed bosh brand.

What is the reason for carbon emission?

I could not pass 600 euro Euro 4 metal convector was installed. I went to the emission in the industry and passed my inspection. Thank goodness to pass at the inspection station.

make a valve