Catalytic converter?

I have a 1999 Chevy Lummina that the converter goes out every once a year for the past three years

The mechanic does a test with his computer tester.

I have taken it to different repair shops and they all tell me the same thing.

I have just over 70,000 miles on it.

That has been the only mechanical problem it has ever had.



What could be the problem ?Catalytic converter?
If you don't use it much, and you have it park outside. they buildup rust faster from humidity..OR take it OFF if you don't have state inpections.Bye universal converters, cost less.try a better gas station...gasoline might be bad.Might be burning too rich too...Catalytic converter?
hey maybe it should have two. if its missing one your making the one that is there work to hard. My car has 4 catalytic converters.

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