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I have a non OEM cat on my 2000, and it's works just fine. Pretty sure it was > $100, but whatever...
Lol Have you just asked on Rennlist about the same problem?
It's pretty funny as I just advised you (I think) to come here...(I have a different name there)
Check the O2 sensors before replacing any cats !!!
Yeah, pretty rare for cats to go bad, unless you ignore an O2 issue forever.
How would you know if your cat had gone bad?
Fairly rare for cats to go bad. Ignoring O2 sensors and running with a misfire for a long time can clog a cat pretty quick and cause other damage. Not to say thats the case here.
First article I found Googling, but there's plenty more. Catalytic converter seller on Ebay:
Cats don't fail, something else causes them to fail. Just pointing this out in case your cats have indeed become clogged, whatever is causing it will do the same to the new ones you put in.
When you changed your O2 sensors what brand did you use?
In my experience you should stick with Denso as some other ones can cause problems... just my $0.05
I always take care of my cars as promptly as I can. I bought the O2 sensors at Autozone, so not sure about the brand. Unliley for them to damage the cats though.
Checked with the master Toyota technician of several years and was told common for them to go bad as he has changed them quite often.
Per Toyota tech, common so not to worry about other things causing cats going bad. I have always, I mean always, used the premium gas and had recently (last year) spent over $1700 for a complete engine service including but not limited to changing the timing belt, water pump, plugs, fuel filter, all fluids changed including the AHC service to name few.
The link ^ does make sense and I think the problem could have been the O2 sensors bought at Auto Zone .
At autozone and dang it, they could have caused all these problems.
. Unliley for them to damage the cats though.
Those two codes, 0430 and 0420, are cat efficiency codes, not cat failed codes. Both banks are reporting the same efficiency DTC so you have to find what the root cause is upstream. Likelihood of both cats just happening to fail without a common denominator issue is pretty slim. You need to look at your LT fuel trims and o2 sensor output voltages to start with. The fuel trim numbers will tell how much extra/less fuel is being delivered to maintain the ideal A/F ratio and the sensor outputs will show response voltages to varying engine/temp conditions. TechStream will do both for you and I'm sure there are plenty of OBD2 plug in Bluetooth monitors like scangauge (that I have no experience with) that will allow you to do much more extensive diagnostics. Certainly your cats could have been damaged by, say, burning coolant or a lead additive, but I'd eliminate potential upstream issues before swapping them out.Truck has almost 200,000 miles so mileage has nothing to do with the wear and tear on cats? I really can't think of any mechanical issues with the truck (out of tune/plugs/gas) etc that could have caused the cats destruction.
Would bad O2 sensors throw these codes (P0430 and P0420) which are catalytic converter efficiency codes?
Shall I check the O2 sensors even though there are no such related codes and how shall I test them?
On a same note, how can I check the A/R ratio to see if it's WNL (not tunning lean/rich) that could cause the cats damage?