I have 2001 maxima with y pipe, b pipe, Remus muffler and everything is 2.5 inches. Yesterday I installed a test pipe and right now when I accelerate hard I have buzzing noise (bzzzz). I believe it comes from my muffler, but not sure. Does anyone know what the problem and how to solve it, that would be really helpful.

 

well, since you replaced your cat with a test pipe, I would guess that the bolts that hold the test pipe may be loose. Also, did you remember to install the gaskets when you installed the test-pipe?

 

Yes,installed everything. And I can hear that noise comming from the muffler. Can it be that muffler cant hold that much air?