2006 Lexus RX330 code P0430 (B2) Emission System

Question

2006 Lexus RX330 code P0430 (B2)

The car is recently bought. I don’t know about maintenance history.

Oil and MAF and Air filter and all O2 sensors replaced recently.
O2 are new genuine and working good.

Are there any other issues that can be related before changing the Cat?

How do I diagnose reach/lean if it’s maybe an issue?

Can a bad PCV valve create this issue as well?

Answer 1

Are there any other issues that can be related before changing the Cat?

Yes, you can use high octane for a couple of weeks, and if possible, add a fuel additive. Also, check for leaking exhaust pipe. 

How do I diagnose reach/lean if it’s maybe an issue?

With an OBDII scanner, it is possible to read the fuel mixture

Can a bad PCV valve create this issue as well?

Yes, it is possible, but not likely. I have never seen a PCV valve setting a P0430 code.