Seat Toledo (Problems with CO2)

Hello friends, I wanted someone to guide me about a problem with Seat Toledo 1800 Gasoline Injection (I am totally profane in mechanics). I have been having the ITV for excess CO2 for the last two years. Two years ago, after trying to pass it by adding products to gasoline I took him to a "specialized" injection workshop. After changing spark plug wiring and almost "half motor" I managed Injectors ... I have to pass the ITV this and I'm already trembling. Orienting what it may not have to repair it for trial and error.
Thank you very much for reading all the pamphlet. (I have changed the catalyst about three years ago)

I understand that you are profane and not wanting to be pedantic, what you have is CO problem, which is what they control you in the ITV ... I comment, excess of CO is usually that there is a lack of oxygen in the mixture .. or bad information about the amount of oxygen ... I would look at the air filter and Lambda probe, a clean injectors would not go wrong and it is cheap ... anyway it is logical. that tests the injection in case it has any defective sensor.
As in the first they charge you and you have two opportunities to go to the cheapest I would buy the clean injectors and change the air filter if it touches it, and then make about 20 km and give it a little cane uploading it around before reaching the ITV. If they throw you back, take it to the workshop and check the lambda probe and the sensors ... luck

Friend as advice rather than sure to pass the ITV, I recommend that you change your catalytic, that is to say the catalytic converter, the gases would lower you markedly, that is, if you are in 600, I leave them in 90 as a cash I do it all the time in my workshop and it does not give any problem, once you change it you must take a long turn so that it enters working temperature before going to the ITV catalytic, and you are already approved.