P0420

Getting the P0420 code on my 2022 Hybrid. I have 44K miles.
With only 44k miles is it conceivable that the Cat could be bad? I doubt that.
I've tried the CatCleaner and i'm finding that the code still repeats every so often.

I've been resetting the odometer as soon as the check engine light comes on.
Then I read P0420, and clear it with my cheapo code reader.
I have gone as much 260 miles before it repeats, and as little a 25 miles to the CEL.

My new code reader (Ancel B200) gives me bank 1 and 2 sensors.+
How many O2 Sensors are on the V-6?
I haven't crawled under it to examine the exhaust system.

I'm tempted to replace the downstream sensor.

Or should I try that "sensor extender fix" folks talk about?

It's pretty annoying. When it happens I lose cruise control, but it seems to run ok otherwise.

Anyone else experiencing this?

Your thoughts

 

It's possible the cat is bad

 

Along with other emission control devices, federal law requires manufacturers to replace a defective converter for up to 15 years or 150,000 miles.
Does this indicate that I could have mine replaced by Toyota under warranty?

 

I thought emissions related items were only covered for 8 year 80K miles, but it may vary by state. But 100% the cat is under some type of warranty

 

Depends on the state... Cali I think it's 7 years 70k, for whatever reason I thought it was up to 100k, but that was probably before cash for clunkers.

 

If cat is bad under 8/80 warranty then Toyota will replace it. Now since you dumped in some kind of snake oil cat cleaner, well that’s a different story lol. You can open the Toyota app and look at the emissions warranty and all the parts covered

 

My experience with P0420 has almost always been it's an O2 sensor either before or after the cat that causes it. The only time it wasn't was when I bashed a Subaru cat and it rattled away. Whatever the cause it should be covered.

 

I have an upcoming appointment with the "Stealer". We'll see what they conclude.
It is 80K miles on the Powertrain which appears to include the Catalytic Converter, not sure about O2 sensors.

...Hey GreenPus: "what they don't know won't hurt me "
After using the Cat Cleaner, I went 120 miles without the CEL.
So I thought maybe I cleaned the Cat or the Sensors, as supposedly advertised.
And sometimes certain functions are polled by the ECU at mileage intervals.
But now, based on closer examination of ODO resets between Cels,
I see that the Cat Cleaner did not fix anything.

[I've been resetting the odometer as soon as the check engine light comes on.
Then I read P0420, and clear it with my cheapo code reader.
I have gone as much 260 miles before it repeats, and as little a 25 miles to the CEL.]

...and SteveH: I haven't been boony bouncing, so there's no way I bashed the Cat. All street miles.

I always start with the cheapest fix and work my way up. ($20 for the Cat Cleaner)
But replacing a CAT? ($1K), I'm glad that would be on Toyota.

I will update after the appointment.

Thanks for the replies, Guys! I appreciate your input.

 

Toyota had it for a day, and got nowhere. They reset it and it would not come back after 22 miles...so I drove it another 25 miles and it came back. It is not instant, but I knew that and told them so. Their excuse, "it is intermittent". Since it was a Friday, they offered to keep it over the weekend even though they do no service over the weekend. Sheesh! So now they say "bring it back Monday if it happens again so we can diagnose it". Come On! It's classic P0420 symptom. The code reader will not read different, so take action!
I hope they replace the O2 sensors to see if that does it. I would, if I had to pay for the repair.
But it is on Powertrain warranty so not out of my pocket.
However, they charged me half price for an hour of their time, on the assurance that once fixed they will refund me.

It's not over till it's over

 

Sometimes it doesn't come back on immediately. It takes a few starts or a few miles, I'm not sure how it determines how long it takes to show the code again, but a code reader will tell you "not ready."

 

So,
I have had the bank 1 Cat replaced in resonse to a repeated P0420, and after about 20 miles got the P0430 .
I hadn't seen 430 on my code reader ever.
Brought it back in and they diagnosed that the other Cat needs a replacement. (Both done on warranty, Phew!).

This is strange, isn't it?
Each time they have given me a free loaner, so they are treating me right.
But 2 Catalytic converters gone bad?

They say their history read of codes indicates that Cat2 was coding prior to Cat1 coding.
My code reader doesn't do history.
When Cat 1 coded it became more frequent and led to a noticable decrease in performance and gas mileage.
After the Cat 1 replacement I was seeing much better gas mileage, a bump from 12 mpg to 18 mpg under the same driving route conditions.

Then a day later, came the P0430. I thought maybe they should have changed O2 sensors. Not reailizing that this code was for the other Cat.
I takes a day for them to diagnose, and order the part. Another day for the part to travel, and the third day to receive it and install it.
So each of these events has cost me 3 days without my truck. But the free loaners help a lot.

I just don't get it. 2 catalytic converters gone bad within my first 43K miles.
I'm not seeing others experiencing this issue.

I'll update after I get it back with 2 new Cats.

 

Cats tend to go bad if your engine is running rich all the time

 

Ok Knabores,
BUT
why would I be running rich?
And wouldn't I have registered the codes a lot sooner if I was running rich?

 

Generally it’s upstream O2 sensors that dictate fuel trims

 

I just find it funny a 420 code is about oxygen sensors.

 

thanks Knabores,
that's food for thought but,Since both Cats are being replaced, would that mean both upstream sensors went bad and caused a rich fuel mixture?
It is beyond coincidence that both are being replaced at 43K miles.
I'm concerned that we are fixing the outcome and the root cause may persist.

 

100+ miles so far with no codes. Both Cats replaced on warranty.
No clue why both went bad, but as long as I don't code again I won't try to figure it out.
I am always asked if anyone else has had this experience.
It does not appear so, monitoring this and other Gen3 Tundra forums.
GREAT! I'm a first......ACK!

 

I"ve seen exhaust leaks, which cause the motor to run rich, register a P0420. Could be by replacing the cats, they fixed the exhaust leak(s) Just a thought...

 

These new Cats are burning in. When I come to a stop I can still smell their heat.
My gas mileage is back to normal.
I haven't towed yet, and have not traveled an extended distance.
I've just been running around town and it is winter cold so I expect it to be a while before they stop smelling.
I won't park on grass, because I don't want to be on the news for starting a fire.