How long are your cats lasting?

No, not those kind of cats ▲▲

My CEL recently came on, and the scanner read:

P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0430 Catalyst System Efficiency Below Threshold (Bank 2)

I am just curious to find out if anybody with a Second Gen has had to replace their catalytic convertors yet. Is there another issue such as an exhaust leak, bad gas, or bad O2 sensors that you found were the cause of the problem?

I have a 2006 Tacoma with 200k miles on it, so I am not saying there is no way it could be my cats... Just wondering if anybody else has had this problem. Also, the CEL has turned on and off a couple times. Both times it came on I was driving on the FWY at a slight incline (same exact time and place), the weather was also cool.

 

Cats are warranted to 80K by Federal mandate. For 200K, I would consider them to have had a good life. Easy clue to bad cats is a rotten egg, sulfur smell.

Work your way from the back to the front on this one. The rear cats are not monitored so I don't see them as being an issue. The rear O2 sensors are relatively inexpensive compared to the fronts. Finally, hope the front cats are good. With them being part of the exhaust manifold, thats the high dollar fix.

 

no way it's your cats, fork $150 to toyota partsman and get a new O2

air fuel and o2 sensors, both went between 130,000 and 145,000 miles

a/f first, o2 was next.

got p1135 on a/f and p0420 on o2.

I changed sensors without a second thought. reset ecu. all is well


Cats ? still on original set, still pass emissions, no codes since i changed
the sensors with OEM toyota sensors...210,000 miles now...no issues


I am guessing it is just the 02 sensor because they die at average age of 130,000 miles,
it is a plain fact they do not last forever and unless you have a history of bad gas, or extreme
life of only very short trips ...the cats should last a long time



I even have a period between 2000 and 2004 where I raced 2strokes, and needed a place to
dump a gallon or so of 50:1 premix every weekend for 4 years...so into the 4runner tank it went
and filled up with 87 octane to mix it. cats still blow Massachusetts PASS emissions to this day...so no harm there...

 

My oldest is 9.

 

Haven't noticed a rotten egg smell, and the codes are for the front 2 cats. I also read in TW (somewhere) that the sensors give another CEL code reading when they go bad. Do you know anything about that?

Price is $1050 for the front cats, that's cost too (my sister and her husband own a Toyota repair shop). So, trying to check every other possibility before I replace the cats

 

Definitely going to check the O2 sensors first. I bought this truck used a month ago, so I don't know what type of gas the previous owner used. I took it to get smogged last month and it DID pass... the tech said it was actually very clean too.

 

My driver side kicked it at about 89,000 miles. I got new O2's and that didn't fix it. Picked up some new gaskets and put the driver side forward cat/manifold on and all is good. The passenger may be on it's way out but I already have that, as well as new gaskets.

 

Wow, only 89k miles?? What kind of gas do you usually use?

 

Regular, most of my trips are more than a few miles. Work was 30 miles.

 

o2 sensor for sure then, case closed.


get one from a toyota dealer specific to your VIN number
this way you are guaranteed -done in one-

aftermarket O2...lots of bad stories



Oh yeah check for exhaust leaks obviously....if you have one
that needs fixing first

 

my oldest is 14+

don't know her exact age, she just showed up and proceeded to have 2 liters in the laundry room. Now she lives on the porch 24/7


you could always try this.. http://www.youtube.com/watch?v=5icTmYItwiE

 

LOL

 

UPDATE:

Being that the O2 sensors were actually giving a reading and the CEL code was for the cats... this ruled out the bad O2 sensor theory. There is actually a code for the sensors.

Next, I unbolted the catalytic convertors and put a snake cam inside. I was surprised at how good they looked! I have seen bad cats before, and mine were far from that. After bolting back up and looking for an exhaust leak (didn't find one), I decided to check the spark plugs. Since I just purchased the truck I wasn't sure what kind of condition they were in. They were completely worn. The original NGK plug (front Driver side) was also never replaced. So I changed all plugs, reset system... and code has been off for nearly 1,000 miles. I blame the CEL code on the old plugs and cheap gas

 

well, don't rule out the o2 sensor being bad, or close to dying, if it throws the code again

there is nothing on the vehicle to tell you there
is a bad cat other than the O2 sensor after the cats. that is all there is...
it will throw bad cat code on a clean cat BECAUSE it can no longer
accurately measure the proper difference between clean air and the cat stream

O2...there is a ceramic element inside and it starts to degrade the moment it
is fired first time at the factory....around 130,000 or so miles it degrades to the
point of throwing codes needlessly

a) before the cats, are the air fuel sensors...basically they are
extremely accurate o2 sensors. they measure how the engine management
is performing and make engine leaner or richer

b) after the cats are the o2 sensors and the only function they have
is turn on the MIL light when the reading goes out of spec, or they
actually break and provide no reading at all

c) both types of sensors simply die of old age...usually 130,000 or so miles
is when they should croak. of course your miles may vary