i have a 99 gxe. basic bolt ons - ypipe, catback, intake.

i have had these mods on for a while, but just now I am getting this weird exhaust noise... like a BOOmboboBOOMbombombm and every once in a while i hear a *pop* coming from under the engine. I looked under the hood, and the engine was shaking more than usual...like it was under stress. And I can smell the scent of gas coming from the engine bay... could it be a leak? or something worse. I am gonna take it to a mechanic but I would like your guys' opinions. Thanks in advance.

 

I think the BOOmboboBOOMbombombm sensor is bad... j/k

Sounds like either an exhaust leak, a misfire or perhaps both?

 

make sure the bolts are tight on the Y-pipe and Cat. Also, make sure the connections on the intake are tight, any vacuum leak will cause a pop-pop-pop exhaust noise due to a lack of stablility.