Clio 182 High CO2

[PeterS_]

Hey guys, im looking for advice,
My Clio 182 is failing mot in Portugal due to high co2, it’s supposed to be 0.30 and it’s double at 0.60-0.70. I have Optimiz acess catalyst converter and exhaust which is as close as we can get to oem quality, brand new Bosch lambda sensors, engine timing is perfect set with oem tools, and I’m not getting any warning on the dash. I also checked the map sensor and the seal is good and tried injector cleaner but still having the same issue.
One weird thing that is happening is when arriving there the idle levels are ok but after checking the levels accelerating the idle gets a high reading too. I’m pushing the car to its limits when going to mot to make the exhaust and cat really hot but no result.. any suggestions? Thanks

 

[mumpy]

Can you check fuel trims via some diagnostic tool?

Check coolant temp sensor readings too.

Does the car idle ok?

 

[PeterS_]

Can you check fuel trims via some diagnostic tool?

Check coolant temp sensor readings too.

Does the car idle ok?

The car idles ok and pulls very well too, I will try to have acess to a diagnostic tool with live data to check those

 

[mumpy]

Another thing, how long have you had your cat? Has it passed before with the same cat? Any chance you could measure the inlet/outlet temperature with some IR thermometer? The outlet side should be much hotter if the cat is working ok (about 100C difference higher on the outlet as a rule of thumb)