CAT Codes PO420 and PO430? Also Key FOB Question

[Mattdamnit]

So a little background I had issues with the SAIS system and did the bypass with the SAIS pump and kit. Now I don't go into limp mode anymore but my dash is still lit up like a Christmas tree. I get the codes PO420 and PO430, PO420pd P0430pd. Would love to find a fix. Thanks for any help!

Also how hard would it be to get a new key fob? I just have a plan key with no unlocks or anything.

And I plan on having the belt and pump done soon, it has 260k miles and I can't find a history of it ever being done :O

 

[HomersCanyonero]

There’s a few ways to try to deal with the cat codes. These are very specific codes regarding catalytic failure, but some say maybe there’s a leak in the exhaust manifold.

Others say you can try antifouler extensions for the O2 sensors. This tricks the sensors. I didn’t do this because I rather fox it right for heath reasons due to smog in the city.

The other way is to replace the O2 sensors and see if that helps. If it doesn’t, you end up with new sensors even if you have to replace the cats.

In my case, I replaced both cats last month and all my codes went away.

 

[Mattdamnit]

There’s a few ways to try to deal with the cat codes. These are very specific codes regarding catalytic failure, but some say maybe there’s a leak in the exhaust manifold.

Others say you can try antifouler extensions for the O2 sensors. This tricks the sensors. I didn’t do this because I rather fox it right for heath reasons due to smog in the city.

The other way is to replace the O2 sensors and see if that helps. If it doesn’t, you end up with new sensors even if you have to replace the cats.

In my case, I replaced both cats last month and all my codes went away.

How much did it cost you to replace your cats?

 

[sampson]

So a little background I had issues with the SAIS system and did the bypass with the SAIS pump and kit. Now I don't go into limp mode anymore but my dash is still lit up like a Christmas tree. I get the codes PO420 and PO430, PO420pd P0430pd. Would love to find a fix. Thanks for any help!

Also how hard would it be to get a new key fob? I just have a plan key with no unlocks or anything.

And I plan on having the belt and pump done soon, it has 260k miles and I can't find a history of it ever being done :O

First thing I’d do is get it up on jack stands or ramps and run it preferably in morning or on chili day. See if you can easily spot any leaks. If there’s a leak you should definitely see it. Most likely coming from one of the gaskets. If you don’t find a leak I’d get a gallon of laquer thinner or caticlean and run it through with a half tank of gas. Clear the codes and see if they come right back. Next step would be to start replacing 02 sensors. (Typically you’ll get a code specific to which one of this is the case. Ie: bank one sensor one) There are 4. One for each cat.

If that doesn’t work you’re looking at about $500 a pop for the secondary cat installation. If it’s the manifold cats you’re probably looking at 2-3k. You can also purchase 02 spacers for about $40 for all 4 and that would fix the codes but no guarantee you’d get through emissions. If you’re going this route depending on your expectations on the vehicle and how long you plan on keeping it I’d punch the cats out so you they don’t clog up as pieces can backdraft into the engine and ruin it. Good luck!

 

[HomersCanyonero]

How much did it cost you to replace your cats?

If you search the online stores, you can find the manifold cats and their gasket for like $500 for each side including taxes and shipped from an online Lexus dealer. I documented in my build thread the part numbers and locations I researched prices.

So, parts a little under $1000 and labor at Indy shop was $200. I did have two shops confirm the codes were for the integrated manifold cats and I cleared the codes like 20 times and even replaced the O2 sensors but that didn’t work for me.

In my case, integrated cats were bad.

 

[sampson]

If you search the online stores, you can find the manifold cats and their gasket for like $500 for each side including taxes and shipped from an online Lexus dealer. I documented in my build thread the part numbers and locations I researched prices.

So, parts a little under $1000 and labor at Indy shop was $200. I did have two shops confirm the codes were for the integrated manifold cats and I cleared the codes like 20 times and even replaced the O2 sensors but that didn’t work for me.

In my case, integrated cats were bad.

You paid $200 labor to have 2 manifold cats installed on a gx470?

 

[HomersCanyonero]

Yes, $200 total labor for both integrated manifold cats. No rust here though. Just did it like 6 months ago

 

[Mattdamnit]

We don't have emissions here where I live. I just want the damn codes gone. I will try some of the solutions you all mentioned.