Seat Ibiza 1.4, High Co2 readings

[Runner96]

Hi Folks

I am new to the Forum and have encountered a problem with my 2010, 1.4 petrol Ibiza
Which I would like to share and hopefully someone out there may be able to advise.
My Ibiza has started using a lot of petrol, engine shows steady revs, however engine vibrating during idle, black fouled up plugs, no engine warning light showing. recently failed MOT with Co2 readings around 13%. if stopped briefly occasional petrol smell in cabin
I have since changed the Lambda sensor, fuel filter, drained the petrol replaced with super unleaded, changed spark plugs, new air filter, changed injectors, no codes showing any faults starting to wonder about diagnostic kit,
Any advice greatly received running out of ideas and money, in NI

Regards Runner96

 

[queen]

Black smoke coming out of the exhaust?

 

[Runner96]

Cheers for getting back,

When the fuel economy dropped there was black smoke, but it has stopped since then. Although there are carbon deposits on the ground coming from the exhaust.

Regards Runner96

 

[Big Col]

do these have a coolant temp sensor, or similar?

not up to speed on vw group engines but 'back in the day' when I knew my way round a vauxhall engine a dodgy coolant temp sensor would make it run rich.

 

[Runner96]

I changed the coolant temp sensor yesterday as well as putting cat cleaner through it, the sensor looked to be corroded and it seems to be running better now the mpg is still a lot lower than what is expected

Regards Runner96

 

[NetworkMan]

Were all the plugs fouled? Not just one or two?

Does this engine have a mass flow sensor or does it use engine speed and pressure like my 1.2 TSi?