Pesky p0420 code (1 Viewer)

[StaticTorque]

Hi everyone! I just joined the club of owning a Land Cruiser! (1996 LX450) I has the P0420 code for the Cats. From what I know, the engine was replaced about a year ago, it does not have the EGR system on, and both O2 sensors were replaced. Before I jump into replacing the Cats, what are some other trial and error things I can try before hand? Need to pass emissions for OR.
TIA

 

[categorytheory]

1. Buy a FSM.
2. Buy Multimeter and learn to use it.
3. Check specs on your O2 sensors.
4. Replace if needed
5. Win.... .

welcome!! And I just went through the same but with the dreaded P0401...in the end replaced both O2s and cleaned the intake manifold and all is good w the world... for now....

(Customary mud greeting).

 

[jjdeneen918]

I got that same code yesterday.

I cleared it & will see if it returns.

I replaced my O2 sensors about a year ago, so that probably isn’t my problem.

hopefully I don’t need to replace the cats.

mine is due for smog too, but waiting on the Wits End turbo CARB exception before I can take it in.