Hey everyone my car threw a code two days ago and i just got around to scanning it. The code was either P0420 or P0421, i didn't write it down before i cleared it so my bad on that one. My question is basically knowing that some part of my emission system, namely the cat(s), is/are dead is there anything i have to worry about besides emissions. I don't have a smog test for another year and I'm not an environmentalist so if it wont break anything else its not getting fixed.

The car is a 2003 Mitsubishi Lancer (Oz rally, but that's irrelevant) - the car has two cats, one on the headers and the other before the resonator.

The info for the codes if you wish/don't already know:
http://www.obd-codes.com/p0420
http://www.obd-codes.com/p0421

Thanks in advance.

 

Had P0420 at first and then P0421 for like two months. Basically, it says you're front catalytic converter is dying (probably had a crack). They did have a recall on them, but upon calling three different dealerships, they could not find a recall for my car and could do nothing about it. So what I did was the non-fouler trick. Worked very well (~1500 miles since that)

https://www.evolutionm.net/forums/ev...ouler-how.html