if your state doesn't require one, unsure of TN, Maine can't ticket you for not having one. You cant enforce out of state inspection standards here in Maine. IE: it's reg somewhere else but has completely tinted windows or a really loud exhaust or something of the sort. Even if TN does require you to have one, Maine can't enforce that. Not unless they changed something in the past couple years since I was at the academy.it is likely at the flex pipe. that is where those fail all the time. Get the upgraded downpipe from eurosport and put an O2 extender on. you will be much happier with something like that rather than a straight pipe. And you will be legal. Missing cat's is a $2000 fine no matter where your car is registered.
it's an audi. it went boom.