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I diagnosed my 2007 Chevy Avalanche V8 5.3 Flex Fuel when
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98 Astro: spark plugs to a catalytic converter bad..distributor..stall
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2000 pontiac grand prix: 6 cyl..p0420..Catalyst..Below Threshold
my 2000 pontiac grand prix 6 cyl.. i went to get my inspection sticker and it failed because of a P0420: Catalyst System Efficiency Below Threshold (Bank 1). what does this mean and how much would it … read more
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