Taigher

My 03 LX Sedan has 230,000 miles on it. Runs pretty well TBH but the rattling is driving me insane. One persistent source of rattling sounds like bits or metal being rattled in a tin can. If the car is in park and I rev the engine the normal revving sound is followed by the rattling. When driving, acceleration in general results in this sound.

Best case scenario heat shield? Could be catalytic converter or transmission? I checked under the hood and looked at the heat shield on my cat and it's not pretty but it's on there pretty firmly. Sounds like it's coming from the front part of my car. Deep in engine or front undercarriage. Helpers? Thanks

NDNV

Common for heat shields on and around the exhaust system to rust out and cause noise like you describe.
Also check the front brake rotor dust shields for rusting off.

Taigher

I was hoping it's that simple. I'm going to get under my car this weekend if the weather lets me. My understanding is that I don't need them to have my car run and not be damaged? Some guy on the internet said it's for if I park on grass it doesn't catch fire but I don't park on the grass anyway. I'm not a mechanic so what I'll do is get under there and check any heat shields I can find around the exhaust system. If somethings rusting off I'm just going to remove it. I'll google the front brake dust shields because I've never looked at those on my car but I'm sure I'll be able to locate them pretty quickly.

Slumpertcivic