Mini Cooper emissions problem

[lavenders15]

Hi just hoping for some advice as a new mini owner going through MOT stress! and really hoping to keep my car if it's not too expensive.

I got a MINI mini 2008 petrol last year and I've done 3k miles since my last MOT.

It's sadly failed it's emissions tests:

major defects:

Exhaust hydrocarbon content after 2nd fast idle exceeds default limits (8.2.1.2 (b))

exhaust carbon monoxide content after 2nd past idle exceeds default limits (8.2.1.2 (b))

exhaust lambda reading after 2nd fast idle outside specified limits (8.2.1.2 (c))

I had the CAT replaced - and they did other work without telling me prior (replacement spark plugs) but said that they wouldn't have known if the car needed this until the CAT was replaced. cost total £600 now

first the fuel emissions were 90% over the limit and that replacing the CAT brought it down to over 40%, but this still was too high to pass the MOT.

They said they can do further work but it will cost more and isn't worth it for my car.

does anyone have any clue if I can ask for any other tests/repairs from another garage - or if it would even be worth doing? It is a cost issue as much as I love this car - does anyone have a genuine estimate?

The garage kept my car longer than stated so this MOT has now expired and I'd have to arrange a tow/ or pre-book another MOT test.

Thanks for any help.

[un1eash]

Have they checked the pre lamba O2 sensor readings. There may be a problem with the sensor so it's running default fuel trims.

[E-bmw]

Slightly different to the above I would say to check both the pre & post CAT sensors as both will help diagnose if there is any issue with either CAT or engine fuelling.

Other considerations:

Check for any air leaks in the intake pipework or exhaust leaks.
When was the oil/filter last changed?

[lavenders15]

I changed the oil and filter 6 months ago and Garage said they think the only things left is that it might be an air leak or engine issue but that the car isn't worth the cost 😪