What should my next steps be? P0430 and P0420

[K_Labs]

went through the exact same problem with my tacoma and Honda, save yourself the headache, the few hundred if not thousand dollars and get yourself a set of spark plug non foulers from autozone and do the "non fouler mod" explained here.

https://www.youtube.com/watch?v=wcDPAfz10Io


Don't double up the spacers like this guy did, one will do. Guarantee you pass especially if your state doesn't test the actual exhaust gases coming out of the tailpipe, if those are above your states accepted pollution levels and they test those you're SOL. Good luck

Are there any negative effects from doing this?

 

[keptin]

Hopefully they'll work for the OP but they didn't work for us :-( My GF is still having the P0420 & P0430 codes.

Just wanted to chime in on this thread. I've had the P0420 code for a while on my 2005 4Runner. Both the dealer and a third party muffler shop were singing the same song: sensors are a waste of money, you need to replace your cat for $1900 (California emissions) with an OEM catalytic converter, as no aftermarket cats exist for CA 4th gens.

Drove it with the code for a while before I said screw it, I'll give the sensors a go, and for $100 on Amazon replaced the downstream right & left O2 sensors and sure enough the code vanished. It's been clear for two months so far.

These are the Denso sensors on Amazon,
https://www.amazon.com/gp/product/B0016NBBQW

https://www.amazon.com/gp/product/B00199FBQY


Some folks frown upon the part-shotgun approach, but I had nothing to lose using Amazon, and saved $1800 in the long run.

 

[Anteupp]

Are there any negative effects from doing this?

ive had zero negative effects from this, my gas milage has stayed the same and that pesky check engine light is gone which allowed me i to re-register my taco back in SanDiego

 

[chris in ky]

I just fixed my 0420 code on my 2006.

All the VSC and TRAC lights were on. The gas cap was replaced first but still throwing the code. My Scantool mentioned O2 sensors, so after reading a few posts on the matter I ordered a left and right Denso after cat sensors ($100 for both), installed them and erased the stored code.

That was a week ago, all lights still off.

This is my first vehicle with traction control. It's a weird feeling to floor it in RWD on snow and not be able to do donuts in the parking lot. Ditto for moving forward on a sheet of ice.

 

[zonianbrat]

Why not clear the codes and attempt the test for 25+ dollars. That way you will know if in fact your emissions are below state standards. Cheaper than 02 sensors. Plus it sounds silly but I like having something to trip the cel cause it turns off the vsc and I can have fun in snow and mud without it beeping at me and correcting me. Then I can always just reset the code from my phone if I want the vsc back on.

Edit: Sorry, I understand that you probably want your CEL issue fixed. My example is unique to me since I don't mind the cel and being able to spin my wheels.

 

[kevin1285]

So I got the non fouler things, and now I can't get the 02 sensors out to save my life. I sprayed with liquid wrench and let that soak in, and then drove it and cooled it. Got an 02 sensor socket, and still no luck. Would definitely be easier if I had it up on a lift, but don't have access to one. Anybody else have a lot of trouble getting the 02 sensors out?

 

[J-Roc]

So I got the non fouler things, and now I can't get the 02 sensors out to save my life. I sprayed with liquid wrench and let that soak in, and then drove it and cooled it. Got an 02 sensor socket, and still no luck. Would definitely be easier if I had it up on a lift, but don't have access to one. Anybody else have a lot of trouble getting the 02 sensors out?

Tried to do the exact same thing with just crawling under my truck. Same result, the way your body lays/sits there is no way to get any leverage.
Gave up, took it to my shop.

 

[kevin1285]

^Was thinking I'll have to do the same thing, but they obviously aren't gonna install these things that help me evade emissions laws, so not sure what to tell them. I just need them unscrewed. I guess I could just say I need them unscrewed so I can put new 02 sensors in myself, and see if he'll do it. I'm assuming the car will drive back home without them screwed in. It's less than a mile down the street. I know him well enough that he'd probably unscrew them for free or maybe $20, but not well enough that he'd break the law for me. I'm sure as hell not buying a new cat on a car with 300k miles. Is that something like what you did?

 

[paperchasin]

with 300k miles on your car, assuming the cat was never replaced, im pretty sure that it is indeed a bad catalyst....

 

[J-Roc]

I have not done anything to mine yet. Coming up on 150K...I'm assuming it's most likely my cat, but starting with the cheapest first...snowing here where I live atm, wont be doing anything till the spring.

 

[paperchasin]

If you guys can find a mechanic or know anyone with an OBD scan tool that can read live data, you can use it to diagnose whether or not you have a bad cat. If your catalyst is functioning correctly, then the rear O2 sensor should see a fairly steady voltage and should not be fluctuating. However, if the secondary sensor fluctuates up and down in voltage, then you have a bad catalytic converter.

 

[kevin1285]

Update, this little trick worked. Mechanic down the street got my 02 sensors loose for me for $10. He couldn't understand why I didn't want him to go ahead and put in new sensors, but whatever. I took it home, screwed the universal 02 sensor spacer adapter (from amazon) onto the 02 sensors, and have driven a couple days (over 100 miles), and no check engine. Works as advertised. Getting it inspected today. The spacer adapters are the same as using the spark plug non foulers except you don't have to drill anything out, so it's just easier.

 

[J-Roc]

Update, this little trick worked. Mechanic down the street got my 02 sensors loose for me for $10. He couldn't understand why I didn't want him to go ahead and put in new sensors, but whatever. I took it home, screwed the universal 02 sensor spacer adapter (from amazon) onto the 02 sensors, and have driven a couple days (over 100 miles), and no check engine. Works as advertised. Getting it inspected today. The spacer adapters are the same as using the spark plug non foulers except you don't have to drill anything out, so it's just easier.

Did you do this to the O2 sensors coming off the manifolds, or the ones further down under the truck by the doors?
Thanks

 

[kevin1285]

Further back, the downstream 02 sensors. They are the ones that read the emissions after the cat. They are the only ones you'd do this to to fix a bad cat reading code.

 

[J-Roc]

Further back, the downstream 02 sensors. They are the ones that read the emissions after the cat. They are the only ones you'd do this to to fix a bad cat reading code.

Yes sir. Thanks, figured as much but just wanted to make sure

 

[kevin1285]

One piece of advice I would give is to go ahead and replace the 02 sensors when you do this. I put the old one's back on just to narrow down the cause of the code, and it is in fact a bad cat, but these 02 sensors are not easy to get off, so I'd go ahead and put new ones on when you put these spacers in.

 

[J-Roc]

One piece of advice I would give is to go ahead and replace the 02 sensors when you do this. I put the old one's back on just to narrow down the cause of the code, and it is in fact a bad cat, but these 02 sensors are not easy to get off, so I'd go ahead and put new ones on when you put these spacers in.

Think I will go the same route as you and have my mechanic at least take them off for me. Thanks for that advice. I have also read that this trick only works with the original O2 sensors....if you change the sensors you may get the codes to come back. Just something I did see somewhere.
Also, can you post me a link to the exact spacers you got.
Thanks

 

[black4vcobra]

Update, this little trick worked. Mechanic down the street got my 02 sensors loose for me for $10. He couldn't understand why I didn't want him to go ahead and put in new sensors, but whatever. I took it home, screwed the universal 02 sensor spacer adapter (from amazon) onto the 02 sensors, and have driven a couple days (over 100 miles), and no check engine. Works as advertised. Getting it inspected today. The spacer adapters are the same as using the spark plug non foulers except you don't have to drill anything out, so it's just easier.

I had a 430 code a few years ago on one of the cats and I used the spacer for the oxygen sensor and it has worked since.

We don't have inspection here, I just didn't want to look at a check engine light all the time.

 

[kevin1285]

Here's what I ordered

https://www.amazon.com/gp/product/B00OXWYW46/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

 

[ScottD]

You did the right thing - I added spacers to both after cat sensors on my last truck and it fixed what had become a cronic problem - and this is after replaceing the o2 sensors.

Added the spacers and fix the problem. Didn't seem to hurt any mileage or power from the engine.