The Nissan Path

Failed emissions, P0420, bought a Walker direct fit cat from Autozone (best price and actually in stock) ~$260 bucks, then had my neighborhood shop replace it. Passed emissions! I'm curious though... Should I expect improved fuel economy? Smoother idle? Anything?

I don't think you will notice much unless your old cat was really constricted.

Usually the 420/430 codes set due to inefficiency at breaking down the exhaust gas emissions and not so much for restriction. You probably won't feel any difference.

Got it, thanks for the replies...