Hello, I just pulled a fault code from my 98 Silverado with a 5.7 liter. The code is po420 which says, catalyst system efficiency below threshold, left bank. I have no idea what that means, any info would be greatly appreciated. Thank you......Ed
Hello, I just pulled a fault code from my 98 Silverado with a 5.7 liter. The code is po420 which says, catalyst system efficiency below threshold, left bank. I have no idea what that means, any info would be greatly appreciated. Thank you......Ed
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