Quote Originally Posted by JoshuaASE
exhaust leaks make a raddle not clicking, I think you might be hearing a desiel affect, called spark knocking, due to veryyy bad tune up, or timing off, or you got bad u joints, but that also makes a vibration, check your motor mounts, an suspension make sure you dont have anything loose, but we need to hear to make out what it real sounds like, but hope some of these options can help you find out what it is, Joshua

true, but 95% of people don't know the difference between a rattle, click, ping, tick and knock, plus he already knows the cat's clogged.