Thanks for using JA
Is the noise under the hood, or under the vehicle, is at idle or while driving too.
is there any lights on the dash?
Thanks for the reply
this sounds like a faulty catalytic converter or even a broken up exhaust shield.
if its a converter the vehicle will eventually lose power and stall. the shield on the other hand may fall out on its own.
a catalytic converter is roughly about a $500 repair.