Clogged Catalytic Converter? (1 Viewer)

[Sal Paradise]

I have a 2006 Land Cruiser with approximately 265k miles.

I've occasionally received check engine lights indicating P0420 "catalyst System Efficiency Below Threshold (Bank 1)". I also have noticed a slight burning smell in the cabin upon hard acceleration.

Should I have the Cat replaced first? Or is this likely unrelated?

 

[jsloden]

There are several posts on the code. I have been having a fight with the P0420 code for a while now. I've got it now to where it only comes on once every few months, stays on for a couple of days and then goes away. I would first replace your downstream driver side o2 sensor, make sure you don't have any vacuum leaks, Check the exhaust for leaks, the headers are notorious for leaking. I would also check and possibly replace your gas cap. I also ran a bottle of fuel injector cleaner through my system. It still could be a bad cat but I would definitely check all of these things first.