why does the catalconverter gets red hot
It is doing it's job by burning excees carbon & gasses & gas residue from the engine.
If it's glowing red, then you have unburnt fuel getting into the cats and burning it. So you either have a misfire (incomplete combustion) or engine issues. Get it checked out sooner than later.
it's clogged up ,don't drive it like that if you don't want to set your car on fire. you can get an aftermarket for about $100 at auto zone.
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