Still getting a P0430

[BlueMeanies]

I've changed both front and rear sensors and checked for leaks.

The header to cat bolt were a little bit loose, but not sloppy loose. Snugged them up.

When I pulled the front sensor, it looked like it had gotten too hot. The element screen/cover was bulged out on one side.

I also wonder it the shaking from the Sawzall that the guy used to cut out the stock y pipe might have damaged the cat. The cel happened on the way home from the muffler shop that day. Coincidence? Hmmmmmmmm....

Anyone else have any further analisys?

 

[RonJon '06]

That O2 sensor could have gotten hot from backed up exhaust (bad cat). Another possibility is a lean condition caused by a bad fuel injector or leaking intake manifold gasket. If you haven't gotten any lean codes then I guess I would suspect the cat too.

 

[Gecko]

Do you still have cats? I believe this is the code I got when I turned my rear o2's back on while having no cats. After doing the non fouler trick it went away.

 

[BlueMeanies]

No lean codes. I'm going to pop the plenum off this weekend just to make sure the gaskets are doing what they should.

How do I check for a faulty injector?

The cats are still on and need to stay. Going to order a Magnaflow universal cat today.

 

[RonJon '06]

How do I check for a faulty injector?

Maybe just check to see if they are sealed. I replaced all the O-rings on mine when they were off even though the originals looked fine. However without any codes I would have the injectors way down on the list.

If you replace the cat and the code comes back again then I would start looking for something affecting the A/F ratio or maybe contaminating the cat or O2 sensor (oil/coolant). Hopefully it was just time for the cat to go or, like you said, it was damaged from the exhaust work you had done.

 

[MyOhFive]

Are you sure the cats are flowing the right direction?

 

[BlueMeanies]

Are you sure the cats are flowing the right direction?

They are the stock cats. Never been off the truck.
Seems unlikely.

 

[MyOhFive]

I understood from another one of your threads you just replaced your Y pipe, would that not involve re & re-ing the cats?

 

[BlueMeanies]

No. The muffler guy cut the stock y pipe out with a Sawzall. Cut the right side just behind the rear O2 sensor. He did not remove the cats.

 

[Redtruck-VA]

I would check leaks and smack the cats with a rubber hammer to see if they make any noise. I'm guessing cats are damaged.

 

[BlueMeanies]

Can't seem to find any leaks.

Yup. I suspect the cat is done. Maggie 49 state cat on the way.

BTW, I figured that since it was going to the muffler shop anyway, I might as well put a Maggie 22" 12589 muffler in... Ordered one of those at the same time.
Quiet, but I need to drown the Hemi tic somehow.

 

[BigSloth]

A P0430 code is an efficiency code, which is unaffected by actual AF ratios. All your AF control is done by the front O2 sensors, the rears are just there to monitor the cat function.

The only things that can cause a cat efficiency code is a bad cat itself, or exhaust leaks. An exhaust leak at any point before, or immediately after the cat can cause an efficiency code. I think you should find that the cat will resolve the issue, unless there's a leak you can see.

 

[RonJon '06]

^^ I agree the AF ratios are controlled by the front O2 sensors but if there is a problem with the AF ratio it can cause a p0430 code. It's doesn't always have to be a bad cat or exhaust leak.

EXPLAINING TROUBLE CODES PO420 - PO421- PO430 - PO431

 

[BlueMeanies]

Good article. Goes over my head at times though.

 

[JNemec]

Can anyone confirm what size anti-fouler to use to gap the O2? I'm dealing with the P0430 and I can't afford what I really want to do right now (replace the manifolds & Y pipe with Kooks, incl highflow cats). So I'm planning on replacing all 4 O2 sensors with NGKs and will space them off with foulers. It just seems like all of the writeups that actually include the specifics are dead links.

 

[JNemec]

Okay, I figured out the size. I ordered a set on Amazon and installed them this weekend. While I was installing, I realized that the parts that I ordered are actually O2 sensor spacers, not necessarily Anti-Foulers. What this means is that you don't have to drill the 1/2" hole in them (it's already there) and they are long enough to cover the entire sensor, so you probably don't have to double them up on each side. I had already ordered two pairs, and I have to go through emissions testing very soon, so I decided not to risk it and just put two spacers on each sensor anyway to space them as far away from the exhaust as possible.

Here is a link to the spacers that I used: https://amzn.to/2K6X9F1

 

[Marley]

Yes those spacers work just like the non-foulers minus the drilling.
Didn't see them until I already installed the others, doubled up of course.