2013 Toyota Tacoma 4.0L V6 Code P0430

I have a 2013 Toyota Tacoma with the 4.0L V6 with 65k miles. In November it started throwing the code P0430 (Catalyst System Efficiency Below Threshold (Bank 2)).

I took it to the Toyota Dealership and they said it need new Catalytic Converters. I was skeptical because the truck only had 65k miles. Luckily it was covered under the Federal Emissions Warranty and I did not have to pay anything.

1000 miles later the CEL came back with the same code, so I took it back to the dealership and they said it needed new O2 sensors on bank 2. My extended warranty covered this so I had them do it.

1000 miles later the CEL is back on with same code. Dealership says I need a new exhaust manifold on bank 2. This time my extended warranty provider wants to send their own tech out to double check that the work is actually necessary. So I left the truck at the dealership and I am awaiting approval.

I am still skeptical that I need a new exhaust manifold on a truck with 65k miles. The truck runs fine and I haven't noticed any drop in gas mileage. Does anyone have any input on this? Does it sound like the truck could actually need a new exhaust manifold? Any ideas what else it could be?

 

Sounds like the tech using the code diagnosis is just throwing parts at your truck instead of troubleshooting. It will be interesting to see what the EW tech has to say, and whatever he decides to do actually fixes it or your code still comes back. Keep us posted.

 

I miss the days when mechanics actually troubleshooted issues instead guessing at what might be wrong. Hoping to hear back by tomorrow afternoon and hopefully I'll get a more concrete answer as to what is going on.

 

I had an old Cadillac, from the prior century, which was throwing an O2 sensor code. I replaced the O2 sensor but still got the code. After some work the issue turned out to be electrical (spark plug wire). There was misfires/incomplete combustion, which was flooding the cat converter, which in turn caused the O2 code.

 

Flat rate doesn't pay shit to troubleshoot. The tech and the customer lose out unfortunately.

 

Sub'd

 

My uncle happened to come across this in a 4.0 Tacoma with similar mileage. He swapped the O2 sensor sides, problem came back.
He then removed the injectors and sent them for flow testing and one injector from bank 2 was not injecting enough fuel. The injectors got ultra sonic cleaning or whatever it's called and that solved the problem.

 

I miss the days when they COULD trouble shoot them. So much complexity these days

 

Possibly something to do with air- fuel mixture that causing this.
Check your air filter as well it may be as simple as this.

 

First thing I'm going to ask is.....you said he replaced the catalytic converter the first time. Right? And now he wants to do the exhaust manifold? The 4.0 has 4 cats. The monitored one is attached to the exhaust manifold. Monitored meaning the one between the air/fuel sensor and o2 sensor. I have heard of air/fuel sensors and o2 sensors causing these codes. But nearly 90% of the ones I've dealt with is the monitored cat. P0430 would be bank 2. Which is driver side, if I remember correctly on the 1GR.

 

Exhaust gaskets prior to the sensor. My best guess.

 

The extended warranty company came back and agreed on the issue but declined the claim because they said it should be covered under the Toyota manufacturer warranty.

Apparently there is a clog in the pre-cat which Toyota says is built into the exhaust manifold. The warranty company says this should be covered under the same warranty as the catalytic convertors. Toyota says since it is built into the exhaust manifold that it is not covered under their warranty.

My Toyota service rep says he was going to talk to the Toyota warranty people and see if there was any way they could cover it. This sounded like bullshit to me and I imagine I'll get a call back saying there is nothing they can do.

They quoted the warranty company $914, so there is no telling how much they would quote me.

This whole thing feels like Toyota yanking my chain, and I'm not confident that their diagnosis is even correct. They have been wrong the past two times.

Like I said the truck runs fine and the gas mileage has not been hindered and the code only shows up about once every 1000 miles. I may try some other things before I have them do the work.

 

Get a second opinion, a clogged up pre-cat will cause some type of symptom...running fine with the same gas mileage suggests the problem lies somewhere else.
I'm leaning toward an exhaust leak somewhere near the monitoring O2 sensor, it doesn't take more then a pinhole to cause issues. Find a shop that can smoke test the exhaust system.

 

Did they replace all 4 catalytic converters the first time? Or just the rear 2? On the 1grfe each manifold has a catalyst built in so in order to replace the forward cats, the manifold needs to be replaced.

 

I think a second opinion is a good idea. A minor exhaust leak makes more sense than what their diagnosis. @Jeffs68 thanks for the input.

 

They replaced the two rear converters. Now they want to replace the manifold/catalyst on bank 2 because they say it is clogged. I'm doubtful that this is true.

 

With as rich as these motors run, I wouldn't be surprised if it failed, however they catalyst would be burnt out, not clogged up. Both my manifold cats failed around 130k. I don't need emissions where I live so I went with a full header back exhaust system and scrapped the cats.

 

My truck is only at 67K miles so it seems like the they should not be burnt out unless something else is wrong. I did have a large amount of spark knock so I had a TSB performed which was supposed to fix it but did not. I reluctantly started running premium (93 octane) and the spark knock has went away.

I also don't need emissions so this seems like a feasible solution if the pre-cats are in fact burnt out.

 

That's your problem, they replace the 2 converters that ARE NOT monitored, only the front converters are monitored.
In this image, 3 and 4 are the rear O2 sensors (monitors), 6(s) are the rear cats, un-monitored.
Toyota is throwing parts at your truck.

 

Toyota is throwing parts at your truck.

This has been my thought since they originally told me that the cats needed to be replaced. I let them do it because it wasn't costing me any money. That has changed now that it might cost me money.

They replaced part 6 in the image which is covered under the Federal Emissions Warranty up to 8 years/80,000 miles. Part 5 is only covered 3 years/36,000 miles but my extended warranty company says it should be covered.

Toyota has not been able to provide any evidence that the pre-cat us clogged and actually needs to be replaced. I think I will take it to another shop and get a second opinion.