car has been sitting for 6 month sounds loud 10 minutes did it will quiet down but still noisy then when driven it gets extremely loud and now it's so loud when try to accelerate the whole car vibrate
Sounds like a problem with the exhaust system. Check for rusty or disconnected pipes. If the car has been in an unsecured area check that the catalytic converter hasn't been stolen. If the check engine light is on that's a real possibility. Catalytic converters contain precious metals that bring money at the scrap yard. HTH. -Jim
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