Hello I'm Paul and I will help you with an Answer to your Question
you can ask him the code number
if the code is p0420 then the converter is almost always to blame
this code sets when the converter loses it's ability to reduce emissions
it does not generally effect the way the vehicle runs
it only effects your ability to pass the emissions test
just verify it's a p0420 to be sure the converter is bad
you can hold off on repair as long as its running ok and you have no emission testing scheduled
let me know if you need more help
p0420 is rarely a sensor problem
he should verify the function of the oxygen sensors using a scan tool but it is not likely to be the sensors.
the converter can not be repaired they are not repairable there are compounds inside the converter that go bad.
as I mentioned this code sets when the converter loses it's ability to signifigantly reduce emissions and does not effect the way it runs usually.
they do go bad over time being a 2005 it is not uncommon for you to need a converter.
the only thing that would accelerate a converter failure would be an engine misfire or oil leaking into the exhaust..
if the engine is running ok then it's just an aged converter and a very common problem
What do they do with the old converters? Are they worth anything...scrap metal. Should I verify that the replacement converter is what they say it is?
you should replace it with a factory converter
the aftermarket ones will sometimes also set codes because they are not built to factory specs
you should get the converter from toyota
the old converter is worth anywhere from 50-100 dollars but there is generally a core charge on it.. so if you chose to keep it you would need to pay the core charge
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