Catalyst code.
#1
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My check engine light came on so I used an Autozone scan tool. It came up with two codes that both read the same, it said "catalyst below threshold bank 1."
The guy at the store said their tool can be a little vague and it could either be an oxygen sensor or a cat. Anybody have this same code before?
The guy at the store said their tool can be a little vague and it could either be an oxygen sensor or a cat. Anybody have this same code before?
#4
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P0420 is most likely a bad drivers side cat. Cats are covered under the federal emissions warranty for 8yrs/80K. To doublecheck you can swap the rear 02's side to side and see if the code moves.
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I will have to go back and get the exact numbers. If it is a cat I doubt the dealer will replace it, I know they will blame my nitrous. Thanks for the input.
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Ok, here is the exact reading. "P0420 Catalyst efficiency below threshold bank 1" This code came up twice. So if this is a bad cat then it's a total excuse to get a set of long tubes and highflow cats.
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Originally Posted by 2001NBMZ28
P0420 is most likely a bad drivers side cat. Cats are covered under the federal emissions warranty for 8yrs/80K. To doublecheck you can swap the rear 02's side to side and see if the code moves.