You need someone to actually listen for where the noise is coming from, but as a guess, I would start by inspecting the exhaust heat shields. It is not uncommon for them to corrode away around their mounting holes, then rattle from engine vibration. Less common is chunks broken loose and rattling inside a catalytic converter. You can identify that by banging on them with a rubber hammer.
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Tuesday, May 11th, 2021 AT 1:13 PM