I've got an 09 Fit that started throwing a P420 several years back doing local trips in cold weather. A good highway run tended to clear it for a while. Not this year.

I'm in a state that does emissions checks and so I'm looking at replacements. I'm looking at parts from Rock Auto, just wondered if anyone had suggestions for other sources a little less $$.


Thanks

Jim

 

Rock Auto will be one of the cheaper options available, unless you have a scrap yard you can pull a factory cat from. But then you're risking getting another bad cat at that point.

 

It is very unusual that a catalytic converter goes bad if there is no mechanical damage or use of leaded fuel. An your car is only 17 years. I would thoroughly check other possible reasons for the code first. Bad sensors are much more likely than bad cat.

 

Depends more on mileage than age, doesn't it? Especially if you've been running rich for a long time. Cats can only absorb so much before they go bad. And I've seen cats go bad at even 100K miles.

 

If it runs rich, it shouldn't pass the emission test.

 

Fair. It could just be a bad/failing O2 sensor.

 

I don't know if it possible to test a lambda (O2) sensor, but even replacing it is much easier and less costly than replacing the cat. Therefore I'd try that first. Actually I think there are sensors both pre and post the cat. There might be some temperature sensors, which would also cause to that code when not working properly.