GMC Other Repair Question
Well I can assure you the cat is not supposed to glow red. It's probably restricted or you have excess fuel draining into the exhaust system. Based on the code that is being thrown, the catalyst in the convertor is toast.
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In addition to the second post, which I agree with, the true problem probably lies with something else in the fuel/emissions system. (unless the converter is physically damaged due to a hit or something like that) You'll need to fully test out the fuel system, vacuums, etc, to find the cause, or a new converter is likely to suffer the same fate. And you will surely need a new converter to play it safe.
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