SOLVED 3gen PO420/PO430 code 28,000 miles help

my tacoma with 28,000 miles showed a check engine light and the codes were PO420 and PO430. Which is the catalytic converters are bad. I have tried finding a TSB for them or the computer. The codes hit at the same time which indicates a computer issue, but I have not been able to find anything on the forum. I have found this issue on the 2nd gen but usually at 200,000 to 300,000 miles. Has anyone seen a TSB or have had the same issues. How did you fix it. I was on the highway and had the cruise control on and when the "check engine" light came on the cruise control died.
All suggestions are appreciated.

 

Did you hit anything while driving on the highway? Maybe a piece of debris hit the sensor. Crawl underneath and inspect it for damage. I bet the sensor or wiring is damaged, and causing the error message/check engine light.

 

Let the dealer deal with it. Trucks under warranty. It's not likely a cat went bad at only 28k miles.

 

Those 2 codes set together usually don't point to a sensor wiring issue.

 

Yep, warranty 8/80 emission

 

On my tundra those codes were bad O2 sensors. Both fronts if i remember correctly.

 

Yep, not a sensor issue. Take it to the dealer, have then diag and fix it.

 

Put it on a lift this afternoon and no damage or broken wires that could be seen no chewed wires below
or in engine compartment. No exhaust leaks were visible.
The long term fuel is reading -11.7 which means the computer is removing fuel.
It is a 2019 not driven much due to the fuel pump recall that took forever to have
replaced.

 

hooked it up and besides the PO420/PO430 codes it showed this.

 

Ok maybe it is fixed.
Dealer said nothing wrong. Left the dealership and within one mile Check Engine light came on. Went
back and the plugged it in again. Said it shouldn't do that we can't find anything wrong. They cleared
the codes and put a fuel additive in and said drive it for a couple of tank fulls. I drove home and filled
it ( only down a quarter of a tank ) with ethanol free gas. It is available here. I only drive the tacoma
when going out of town, but decided to burn some gas. I drove to Flag about 100 miles away( flagstaff AZ )
and on the way back the Check Engine light reappears. It only took just over a quarter of a tank to
fill, again with ethanol free gas. So now I get serious and drive down to the valley ( Phoenix az ) which
is a couple of hundred miles away. At about 180 miles the Check Engine light go out. I only put in about
3 gallons down there so as to get back with about a quarter of a tank. I then again filled it with enthonal
free gas. So far the Check Engine light has not reappeared.

 

The problem: Back when gas was getting really pricey the current administration announced that
they wanted to up the ethanol content to 25-27 % to lower the price of gas. So some reason this
dropped, I figure the auto companies complained. But in my opinion the watchdogs had gotten
more lenient, or not watching as closely and gas is getting out with too much ethanol it it. Who
knows. But if you get a Check Engine light and both PO420 and PO430 kick on at the same time
run some ethanol free gas for a couple of tanks or the ethanol removal additive. Since if it is a
bad Cat or O2 sensor it should only be one at a time. Both on is the indicator.

 

You're being way too patient with your dealer. 'We can't find anything so here's some snake oil.' is an unacceptable response. Either there's a problem with the cats or with the sensors and with the low mileage you have you shouldn't have to try this and that and hope for the best.

 

What % ethanol was your gas ? There are laws governing this… never heard of a Tacoma throwing codes with the standard 10% ethanol blend in the us.

 

Unknown what the actual per centage of ethanol was. It just appears that it was way too much for the truck.
I know there are laws but having been there some laws are enforced more than others depending on politics.
And this can change with administrations. My big problem, I believe is that I just drive the truck when going
out of town the same tank of gas may last weeks. Usually only need at most a quarter of a tank before it goes
in the garage for a couple of weeks.