Comes from buying cheap cat food at wally world ...............
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P0420 code
Thread Starter
Race Director
Joined: May 2001
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From: Guelph, Ontario
P0420 code
I've been getting a check engine light come and go on my C6 for the past few months so I finally got around to buying my own code reader and it shows a P0420 code (catalyst system efficiency below threshold bank 1) and I was wondering if anyone else here has run into this and what did you do to solve it? It seems awfully early for a catalytic convertor to go bad, with only 62,000 miles on it and considering it just passed an emissions test when I bought the car in April.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
Inspect for the following conditions:
Inspect the three-way catalytic converter for damage (dents, severe discoloration caused by excessive temperature, holes, etc.).
Ensure that the internal three-way catalytic converter rattle caused by damaged catalyst is not present.
Inspect the exhaust system for leaks, damage, or loose or missing hardware (area from converter to HO2S #2 primarily).
Ensure that the HO2S #1 and the HO2S #2 are secure and that the pigtails and wiring are not damaged or contacting the exhaust.
Elmer
Inspect the three-way catalytic converter for damage (dents, severe discoloration caused by excessive temperature, holes, etc.).
Ensure that the internal three-way catalytic converter rattle caused by damaged catalyst is not present.
Inspect the exhaust system for leaks, damage, or loose or missing hardware (area from converter to HO2S #2 primarily).
Ensure that the HO2S #1 and the HO2S #2 are secure and that the pigtails and wiring are not damaged or contacting the exhaust.
Elmer
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
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From: Madison (Huntsville) Alabama
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St. Jude Donor '09
I've been getting a check engine light come and go on my C6 for the past few months so I finally got around to buying my own code reader and it shows a P0420 code (catalyst system efficiency below threshold bank 1) and I was wondering if anyone else here has run into this and what did you do to solve it? It seems awfully early for a catalytic convertor to go bad, with only 62,000 miles on it and considering it just passed an emissions test when I bought the car in April.
We had a 2006 Cadillac RSX and had to replace both catalytic converters (at different times). No check light, but the cats started rattling, like marbles in a can. One was at about 40,000 miles and the other at about 60,000. So they do fail before they should.
Both of ours were covered under warranty, and yours probably will be too. I think emission-related repairs are covered for something like 8 years/100,000 miles, but check your warranty manual.
Heel & Toe
Joined: Dec 2005
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Program
Isnt there a program you can buy to shut off a faulty check engine light? As I know there is nothing wrong with my cats??
I've been getting a check engine light come and go on my C6 for the past few months so I finally got around to buying my own code reader and it shows a P0420 code (catalyst system efficiency below threshold bank 1) and I was wondering if anyone else here has run into this and what did you do to solve it? It seems awfully early for a catalytic convertor to go bad, with only 62,000 miles on it and considering it just passed an emissions test when I bought the car in April.
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Thread Starter
Race Director
Joined: May 2001
Posts: 15,323
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From: Guelph, Ontario
I’m not sure why my 6 year old thread was resurrected but I don’t even have my C6 anymore (now have a C7) and I did end up having to replace one of the cats on the C6 back then.
Team Owner
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From: Below the bottom of Berby Hollow, NYS
Not sure why.
Pro
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From: The Villages, FL
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Does seem to be a lot of threads coming back from the dead lately.
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