2003 Honda Accord LX 2.4 liter. I had an O2 sensor heater circuit engine ligjt for quite some time. I finally replaced the O2 sensor, and now I’m getting a P0420 engine light code (low catalytic efficiency) after a drive cycle. Is there a chance that my new Walker brand, O’Reilly auto parts O2 sensor is bad, or is it more likely my catalytic converter has failed?
I do have to pass emmisions unfortunately, and I’m about 2 months overdue. The car has almost 300k miles, so I’d be happy to just get one that gets me another 2 years of registration. Might go a little better than an El Cheapo Amazon cat though.