Code P0420, Catalytic Converter?

LIBBY MCCALLON

MEMBER
2010 TOYOTA CAMRY
2.5L
4 CYL
2WD
AUTOMATIC
156,000 MILES

I've had to get both my catalytic converters replaced 1-2 times each. Totaling 3 replacements. I’m the 2nd owner of the vehicle, the previous owners didn’t get any maintenance done really whatsoever. So, I’ve been stuck with all the costly repairs as they come up. I’ve gotten my 02-sensor replaced, spark plugs replaced and keep getting the same P0420 code coming up every so often these days.

Wednesday, May 24th, 2023 AT 11:56 AM

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
54,378 POSTS

It sounds like you have an exhaust leak, or the engine is running poorly, how does the engine run? If okay and the cats and O2 sensor have been replaced the only other thing, is it can be a bad PCM because it has lost the ability to monitor the emission system. Here is the location of the PCM and how to change it out in the images below. You can get a preprogrammed unit by searching Google or Ebay.

Here is generic info on the p0420 code:

Faulty catalytic converter: The catalytic converter may be worn out or damaged, resulting in reduced efficiency.

Check out the images (below). Please let us know what happens.

Images (Click to make bigger)