Smart for four 1.1 emissions fail

[vw_99]

Brother in laws smart for four has failed MOT. I told him about lights but never done anything about them.

But the emisions he thought he had fixed before mot.
As in eml light kept coming on and his code reader always said O2 sensor. So he replaced both sensors but still failed MOT. I dont have the figures yet but wants me to get a Cat and fit it for him. Im 100% it is the cat yet and dont want to just thrown the parts cannon at it.

Any other ideas where to look?

Car has meant to have been serviced inc plugs few months ago. But he does do uber eats. So lots of stop start trips.

[Tony1963]

Throw a tank of decent fuel in, take it for a good, hard, 20-30 mile drive. That will help, but no guarantee of passing.

[E-bmw]

Need failure figures to comment accurately but a few other pointers that may help.

When was it last serviced?

An oil/filter/plug change can help.

[vw_99]

I know it has had plugs 2 months ago due to a missfire
But in his eyes thats a service.

I know over last 2 years car has had new sump, clutch and cat back exh. As i got the parts for it.

I will try and get a look at car and fail sheet today.

[stevieturbo]

Absolutely zero useful information there.

Post the full test results.