Lifespan of FZJ80 Catalytic Converters?

[CSA]

Another good way is by measuring the o2 readings after the cat versus before the cat. The computer actually does this for you and will throw a P0420 code if it detects issues

According to my Ultraguage, the truck isn't throwing any codes.

 

[PDoyle]

I replaced the #2 cat because it had a hole in it. Never threw a code but you could hear it.

 

[Bambusiero]

Realize that throwing the P0420 code is a binary (yes/no) state that happens only at the end of a very complicated bunch of very analog chemical and control system stuff, plus a computer algorithm that allows for variation and degradation. You could be running in a very degraded state, just a smidge above the ECMs code throwing threshold. Or - You could be running in a very ideal state, with whole bunch of room above the ECMs code throwing threshold. Can't tell the difference - until you actually see the waveforms that the ECM is evaluating. You'll learn a lot and it's very helpful in zeroing in on what's really going on with these crazy codes, before just throwing parts at it. Plus, it's great conversation starter at parties