P0420 & P0430 codes

[EDECEKO]

2008 4.7L 145k miles

Around August, on a road trip, the alternator shit the bed. Got it towed and repaired. A few hours after leaving the shop, while on my way back home from said road trip, the check engine light came on, as well as the VSC and traction control lights flashing.

Long story short, in the midst of a custody ordeal and the road trip was picking up the kids after petitioning for emergency custody. Haven't taken the truck to the shop because

1. Has run fine
2. With lawyers, alternator repair, school clothes, $ has been tight
3. Been insanely busy with courts, lawyers, getting kids enrolled in school etc.

Alas, time to get the car registered so I went for the inspection and those codes popped up.

I have searched for these codes, and a lot of people suggest replacing the 02 sensors first, before replacing the Cat converter.

When I go to rockauto and search 02 sensors, there are a few ones that pop up. What is the best/correct one? Same question for the CC.

Any other useful tips would be appreciated. I've read where some have suggested this is a very expensive repair, and money is kind of tight for me so I'm trying to do it myself.

 

[Tanker Yanker]

Here's the link to my post about this very issue....

http://www.toyota-4runner.org/4th-gen-t4rs/197246-alternator-p0420-p0430-related.html

I assure you, the codes are faulty cats....O2 sensors won't clear it. If you don't have to pass emissions, you can by an emulator to pacify the ecm, much cheaper and easier than cat replacement. PM me if you need help.

Forgot to mention....if you want to try O2 sensors, buy Denso's. The downstream sensors are the ones that read cat efficiency. Upstream sensors measure unburnt fuel....they are fuel / air meters and not really an O2 sensor. Hope that helps.

 

[EDECEKO]

Here's the link to my post about this very issue....

http://www.toyota-4runner.org/4th-gen-t4rs/197246-alternator-p0420-p0430-related.html

I assure you, the codes are faulty cats....O2 sensors won't clear it. If you don't have to pass emissions, you can by an emulator to pacify the ecm, much cheaper and easier than cat replacement. PM me if you need help.

Forgot to mention....if you want to try O2 sensors, buy Denso's. The downstream sensors are the ones that read cat efficiency. Upstream sensors measure unburnt fuel....they are fuel / air meters and not really an O2 sensor. Hope that helps.

Awesome. Appreciate the info. Not exactly what I was hoping to hear though. Such is life. Any suggestions for cat replacements? Seems to be a few different ones to select from

https://www.rockauto.com/en/catalog...5,exhaust+&+emission,catalytic+converter,5808

Also, is this something I can do at home?

 

[Tanker Yanker]

I haven't done this yet, but I understand it is a very difficult job for even a dedicated exhaust and muffler shop. Problem is simply not enough room between the manifolds and the fenders to get everything apart and back together. As for parts, I am going to do Doug Thorley headers when I do it, and I may or may not even have cats when I get to it....again, no emissions in SW Missouri.

Just realized, you may not know this....on our V8 Runners, each bank echaust manifold is a one piece integrated manifold / cat combo....to replace the cats, one has to remove and replace each exhaust manifold, as they are together. The factory manifolds are a major weak point of failure on our 4th gens....hence why so many on here talk about Thorley headers.

Sorry to be the bearer of bad news for you....

 

[0verland]

Easy fix... If you don't want to replace with DT headers or OEM manifolds just throw on a set of O2 spacers on the secondary sensors. Remove and replace the negative battery terminal to reset the CEL and problem solved.

 

[Inthesticks]

I have the same issue but I don’t have to pass emissions. Do you have a source for the O2 spacers? Thanks much!

 

[Zero0575]

Just google "O2 Sensor spacer" or something along those lines.

Here is an example: 02 O2 SENSOR EXTENDER SPACER STAINLESS STEEL M 18 X1.5 HHO BUNG 44.5mmlongUSA | eBay