Recently got my first check engine light... P0430 and P0420 catalytic converter efficiency threshold codes. Read around on mud and most people pointed to new O2 sensors. Took it to two different shops (both specialize in land cruisers) and both quoted me for new cats... 3600 total. I'm at a loss for what to do here. I have some time (luckily did emissions in May) but I want to make sure I consider all of my options before I bite the bullet on this. Any suggestions for a way forward? Thanks
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
How many miles? You can try replacing the sensors, or you can put spacers on the O2 sensors to desensitize them. You can also be blasphemous and install aftermarket Cats for under $1k that are direct placements. More Information for AP / EASTERN 644205 - https://www.rockauto.com/en/moreinfo.php?pk=13749057&cc=1431000&pt=5808&jsn=864
My LX had the Eastern Catalytics installed when I bought it about 7k miles ago and it runs great. Cats aren't rocket surgery.
My LX had the Eastern Catalytics installed when I bought it about 7k miles ago and it runs great. Cats aren't rocket surgery.
FWIW, my 07 threw a PO420 code last summer. I replaced O2 sensors and did not fix it. Ultimately I read @2001LC s post on spark plugs loosening. Sure enough, one on the driver back had backed out, gas was bypassing it, and my trims were off. Mechanic thought that eventually wrecked the cat. Might not be the issue, but checking fuel trim might help rule out one thing that could damage your cats.
Rock Auto. Purchase the Denso brand.
Edit: Sorry, you want spacers? Maybe buy extra gaskets and stack?
Last edited:
2001LC
SILVER Star
These factory CAT are top shelve and don't just go bad, in first million miles.
So we must find reason, they did, or we kill replacement CATs. Which 98 out of 100 instances, is upstream issue. Number one, issues I've seen in 98-05 4.7L 2UZ-fe, that kills CAT. IS: Bad MAF sensor. These can take out one or both CATs fast. Raw fuel gets inside CAT, igniting and burns them up. But that just one issue. Bottom line, keep your engine well turned.
The 2 out of a 100 not upstream issues. Are typically something like: Flood waters fiil exhaust, sediment contaminating. Or rodents building nest in exhaust, clogging. Or Impact busting CAT material.
So we must find reason, they did, or we kill replacement CATs. Which 98 out of 100 instances, is upstream issue. Number one, issues I've seen in 98-05 4.7L 2UZ-fe, that kills CAT. IS: Bad MAF sensor. These can take out one or both CATs fast. Raw fuel gets inside CAT, igniting and burns them up. But that just one issue. Bottom line, keep your engine well turned.
The 2 out of a 100 not upstream issues. Are typically something like: Flood waters fiil exhaust, sediment contaminating. Or rodents building nest in exhaust, clogging. Or Impact busting CAT material.
