[ubermage]

my muffler or something in the exust system sounds like it is coughing when i rev the engine too high, and let it drop. it doesn't happen when i rev it, but it does when it starts to calm down. i took it to a monro or something and they showed me the under side of the mustang, there's no carbon at all except for on the tailpipe. he said that everything looked really good and he didn't think there was anything wrong at all. i'm guessing that he would have tried to find something wrong if he could to make some money, but i guess there's nothing wrong, however i still hear it. my friend seems to think that it's "backfiring" or something. do you guys and gals have any clue what could be the problem?

ps, it's a 99 v6 stick

[Vortex]

is it kind of like a gurggle and settles down with the rpm's?

[ubermage]

actually yeah, very similar to a gurgle.

[Vortex]

the gurgle sound is just the cold air and hot air swirling and makeing a sound less potent, but similar to thunder. it harms nothing, its just an annoying sound that is made sometimes... ususually its with aftermarket exhausts tho.