p0420 code

pops comes home and says check engine lights on..I scan it and it comes up with p0420 code, catalyst something..I forget now.

2002 3.4L 100K miles.
already replaced the first (02?) sensor upstream
Could it be the one thats behind the cat gone bad now?

 

sorry to tell you bro but thats a cat failure code. best thing to do is clear it and see how long it takes for it to come back. if the 02 sensors are good the only thing that will make that code pop is the cat itself and thats $$$$$

 

That's actually not true. The shop manual says to check for exhaust leaks before doing anything else, that's what caused my code last year. I asked this question almost the same time last year:
http://www.tacomaworld.com/forum/1s...eck-engine-light-after-frame-replacement.html