I just got my 2008 Fit on Tuesday, and the CEL came on last night ran the code P0420 Catalyst System Efficiency Below Threshold (Bank 1) so took it to the dealer and the Cat went bad. The car only has 30k any ideas how or why? Or just plain ol' factory defect?

 

im gonna go with factory defect, iv had many hondas with well over 100k, one had 245k stock orginal cat lol

 

If you didn't get a CEL prior to the cat going bad, then it just sounds like the cat was suspect itself. The only things that can make it go bad prematurely would be over fueling for too long and clogging it up, or severly underfueling, in which it would oxidize and pretty much corrode internally until it clogged. But like I said, it seems like just the convertor went out on it for some defect. I haven't run across any recalls or anything on them at the Honda dealer. Did warranty cover it?

 

Yea, my warranty is covering it, also glad i got the Honda Care package and extended the warranty (rental car shenanigans in the rental for sure) . Ive only owned it for a few days and Im in love already with the tiny thing and i miss it hahahahaha