08 v6 check engine code P0430

[cangler]

08 v6, close to 150K miles, noticed the check engine light came on while on the highway tonight, checked the code and reads P0430 - Catalyst System Efficiency Below Threshold Bank 2 was planning to take it into the mechanic but afraid may be costly repair, anyone else experience this on their 4runner? trying to get ideas of what it could be...etc.:frusty:

 

[cangler]

took it in to see what the mechanic would say... had just told him the code it was reading and he just replied "catalytic converter needs replacing" and he quoted $750 replacement part or "weld on" method for $400, going to get second opinion :frusty: maybe it just needs cleaning or "bad" sensor...

 

[lightfreak]

First check for exhaust leaks , a very slight leak can cause this code to come on.


If no leaks you can try changing both downstream O2 sensors. Not difficult to do yourself but you’ll need an O2 sensor tool. Get Denso sensors , which are OE for Toyota. Don’t buy them at the dealer, it’ll be around double the price.

I had the P0420 code come up periodically , same code as yours but for Bank 1. I changed both downstream O2 sensors and the problem hasn’t come back in over 6000km.

 

[jdmsneakerz]

I just had this code pop up a couple months ago. I went to my local muffler shop and he suggested changing my o2 sensors first, being that i'm in CA, the cat can only be purchased through dealer. I went ahead and replaced my o2 sensor (downstream bank 2 = driver side), cleared the code and it hasn't come back on since. I plan to changed the other 3 since i purchased all 4. I got all Denso o2 sensors.

 

[cangler]

thanks for the suggestions guys...

last night, noticed the CEL still on, but this morning it was off... hmmmmm

if it's faulty or dirty O2 sensor, could it trigger on/off CEL? what about exhaust leak?
i really doubt it's the actual CAT, they're supposed to last! i did find this YT video....https://www.youtube.com/watch?v=es9ItFprLZk

 

[oljedi11950]

1st do a goggle search & you'll find mostly o2 sensors & very cheap fixes !

 

[cangler]

CEL came back on yesterday, exactly a week later of it being off..:crybaby:

 

[oljedi11950]

A ton of info on this so goggle search it , probably throw up there's so much ! Some easy ones are spark plug foulers (cheap too) . Rear are o2 easy change out front are air/fuel & are a beach to change , usually better to replace all 4 . Amazon or rockauto best prices I've seen . Denso is oem

 

[TowMeOut]

Mine popped the P0430 code about a month ago. I started freaking out too about the prospect of replacing a bunch of parts. I picked up an OBDII dongle and the "Torque" software for my phone so I could do some troubleshooting (lots of YouTube videos). So far I'm seeing that one bank efficiency isn't as good as the other. However, so far the code hasn't come back.

I haven't had a chance to do a full exhaust leak check yet. That will be my go-to first step if/when the code comes back but so far so good....

 

[cangler]

im trying to keep this 4R as long as possible, so maybe i should just replace the bank 2 cat and the rear 02 sensor, then see how it goes... i can get new cat (eastern catalytic direct fit) and denso sensor from rockauto and find a local mechanic to install that would just charge fair for labor. My understanding is cats don't just go bad unless something causes them to, so need to figure out what may of caused this cat go bad if that's really the case... I've had an afe cold air intake (grey dry filter) in there since 2011, been using a set of ngk iridium spark plugs for the past 70-75K miles, and never changed the ignition coils, says avg 20.1 mpg , just thinking out loud.....

 

[lightfreak]

Your cat isn't necessarily bad.
You can check the temps of the cats after driving for 30 minutes with an IR temp gun. $20 on amazon.

P0420 and P0430 codes are common on older Toyota's and it's usually just tired downstream O2's throwing false signal. Change both downstream O2's and go from there. Aftermarket cats have nowhere near the same precious metals and will fail at some point, just a matter of time. Only change the cat as a last resort.

 

[flyrv9]

On the 4.7 V8 each of the 4 O2 sensors (one in front of the cat and one behind on each side) throws a different code that can be read with an OBDII reader. I have replaced 2 so far. The ones that you wire yourself are much cheaper and just about every auto parts store has them. Just splice the wires to the old connector and you good to go. Remember to use anti-seize on the threads. You will need a special socket (that has a U cut out of the side to allow for the wires). I think it was about $15.

 

[cangler]

long story short, replaced that driver manifold-cat with OEM and also had to replace the fuel/air sensor since it was "frozen", total cost of the repair $730 but will sell my old cat to get some money back. hopefully im good for while.