code P0420 on 2003 nissan altima

[Michael Sackstein]

Yep it’s bad. Time for a new catalytic converter. And you wanna replace it sooner rather than later because those altimas are notorious for sucking the internal comb part of the catalytic converters into the engine, and then you have to replace the engine. So you don’t want it to get to that point. I see that a lot on Nissans, especially the altimas.