Exuast noise/leak?

I have a96 acura tl 2.5 with 135,000 miles on it. I recently had the little muffler that is right after the muffler, looks like a little round muffler replaced with a straight pipe. I did that because it was a liitle loud. But there is still some noise sounds like puttering noise from under the engine around the exuast manifold?I heard that is where most problems of this kind come from? And would a leaking bad exuast or manifold make like ticking noises and also puttering, puffing noise? I need help!