Umm i just installed aftermarket headers a week ago on my full cat back exhaust. The headers and muffler piping and exhaust diameter is all 2.5,

When i started my car after puting the headers on it was loud, but now it sound stock or quiet. What could be the problem?

 

You had a leak, and it sealed itself ?

 

umm were could i cheak the leak? My catalytice converter was a little rusted, i think when my car was loud it rumble and made a hole??