Q: loud noise on 2007 Cadillac CTS

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
car sounds like a race car without a muffler. is it the muffler or do i have some kind of compression problem.
(1) Answer
If seems to run ok and no check engine light then I assume you have exhaust problems or oxygen sensor came out.