Hi, just wondering if anyone could shed some light into my problem. I have a ford focus 1.0 turbo 125cv (I think) which just failed mot for exhaust gas co2. I've attached the test if anyone wants to look at it. Now the problem is that the garage seems to think it is a catalytic converter issue, but the car has done only 41 thousands miles and it's quite new... Does anyone has any idea of potential root cause or reliability of these catalytic converters on the focus? 

The garage wants to add some cleaner product and take for a ride tomorrow and try again. Any ideas here? 

Hi,

Just to be clear.  It is CO (carbon monoxide) that it's failed on, not CO2 (carbon dioxide).

The cat should convert CO into CO2.  It does look like that's not really working at all with such high levels of CO on yours.

HC's also look very high, albeit within allowed limits.

Makes me suspect two things - first check the oil level, as it might be burning oil if it's overfilled.

Second replace the spark plugs to get a cleaner burn in the cylinders.

Lastly, the cats on the older 1.0 EcoBoost are known to wear out early.  But I think yours is the first Mk4 I've seen with this issue.

Thank you @TomsFocusI will give it a try before messing with the Cat. I did service it before mot, I'll check tomorrow if they overfilled it by any chance, if not spark plugs it is.

Also someome advise me to the the garage to check the MAF/MAP and lambda sensors as well. 

Hi @Elovatel is this the first year that you have MOT'd this car ?

Have you any previous MOT history of the car ?

Hi @unofix, it's my third one and first failure. The car has been great, although I did notice the mpg has come down just a bit (0.5mpg average) since a few months ago... Maybe not burning as efficient? 

Hi, thanks for the info.

I had been wondering if a previous owner had tampered with the cat, but if you have MOT'd it before that can be ruled out.

As Tom suggests change the spark plugs first 👍

Yes, as @TomsFocus says, definitely change the plugs, check the MAF sensor is clean and the air filter clean and not damp

Put a tank of E5 in and go for a nice long run and give it a bit of stick - plus 4,500 RPM

Hi all just to give quick update, took to the ford dealership, which took about 20 days for the diagnosis team to be available. 

They updated the power control module and worked fine, passed the mot without any faults.