jklit

I installed a new exhaust on my 1992 Honda Civic VX. It was an aftermarket exhaust from K2 motors that fit pretty well, but tightly. I replaced everything (installed new header, cat, resonator, muffler etc)

After starting it up it sounded good, no noise, i revved it up and let it run a bit before turning it off.

Then when I went to test drive the car 10 minutes later, the car started to rattle. At first I thought well maybe the cat was broken during shipping or install, but the sound seems to come from a different area that is hard to pinpoint, but sounds like from under the engine.

I feel like it is most likely a heat shield or other piece vibrating near the exhaust. My other guesses at the cause: maybe a chunk of metal from the manufacturing flying around in the exhaust and rattling., or a broken cat (is this really that easy to do??), or possibly the exhaust is too tight? or not hanging well enough (i used the existing hangers though they stretch quite a bit to hold).

Any ideas as to the cause of the rattling?????

any input is appreciated.