I was on a road trip the over the weekend, when half way into the trip my "check engine" light flipped on. So at my first opportunity I stopped by a Schucks Auto Supply to use their device to hook up to my cars computer. The error code that came back was "420" which, after I got the print out, I found out it deals with the catalytic converter. Seems like my catalytic converter is working fine though, no rotten egg smell. My dad thinks it might be a bad oxygen or solenoid sensor. Just wanted to hear other peoples input if you have experienced this. I am open to any and all advice... Thanks!

 

Dude 420 man!! It's cat converter ineffiecency. Usually when you have an upgraded exhaust. When I put my Borla header on it tripped on me. Also common if you have a TBE on a WRX if i'm not mistaken. You should search it's covered everywhere.

cheers

garrett