Yesterday, I took the muffler off of my 1994 Trans Am. I just unbolted the muffler and tips, so the pipe now exits right in front of where the muffler used to be. I may eventually have to get new pipes, but for now I wanted it to be louder so I did it that way. It sounds great and I couldn't be happier, only there's a terrible rattling noise, typically when it's idling and when I'm moving at very slow speeds, though I can occasionally hear it while moving faster. I'm not quite sure how to describe it, but it's really annoying and is taking away from the (semi) straight piped excitement. Does anyone have any idea what this could be?