jbrittmart

I'm getting a PO420 error: Catalyst system efficiency below threshold (Bank 1).

I know the dealers recommend replacing the Bank 1 exhaust manifold with the catalytic converter. They want to charge a ridiculous amount for this, of course.

My questions:

Do people have experience using an exhaust shop and just having the catalytic converter cut out and replaced and not fooling with the rest of the system? Is this a viable fix? Are there still chances this won't fix the error?

The LS460 has over 200K miles...is there any real reason why I can't just ignore the issue. Will further problems be caused by ignoring it?

I've also read places that people have simply put in a cheap $10 spacer on the sensor and that will completely keep the error code from ever popping up again. Is there any truth to this?

Thank you for any advice and input.

BB9

It is possible to trick this system with the O2 sensor adapter that will be showing everything OK even if catalytic converter is completely gone. It is also possible to flash ECM and make it to ignore O2 sensors altogether, cut catalytics out and insert straight pipes. In either case car will no longer run as good as it should, it is also illegal. You can try to get used cat from the salvage yard of some sort. Other option is aftermarket cartridge. Exhaust shop should be able to cut yours out and installed generic cartridge of appropriate size. Don't know how much would they charge for the labor though.

jbrittmart

Do you have a link to the correct spacer adapter? Would I need to install the spacer adapter in the upstream sensor or downstream or both? Might you have instructions or advice on where to find the Bank 1 sensor and how to install the spacer adapter? I would like to go this route, but at a loss as to where/how to start.

Currently I just have a bluetooth scan dongle installed and I just erase the VSC error code using my phone whenever they pop up every week or so.

Boykie

As messing with cats are pretty illegal almost everywhere I don't think anyone here got a turn key solution.

JohnnyC407

This is what I used on my 4Runner. Just undid the sensor, drilled out 1 of the non-foulers and put them back in. All 3. You can search for $10 Fix to the failed catalytic converter. Had it in a year and no issues. I have no knowledge of the size of the sensors on a Lexus but it's worth a try.

10$ fix to the failed catalytic converter - Toyota 4Runner Forum - Largest 4Runner Forum (toyota-4runner.org)

Spark Plug Non-Fouler | 42009 | Spark Plug Non-Foulers - 18mm Gasket Seat | Dorman Products

Thienson

My 2010 LS460L engine light on B1S1 O2 Sensor I cleaned the battery post and cable the engine light is off
Try it see it works for you.