ok, my 95 accord lx was making this buzzing/rattling noise when the rpm hits 2000 or 2100. i used to own a 94 accord lx years ago and it did the same thing. the problem was the catalytic converter was bad. so over the weekend, i replaced the cat converter and it still make the same noise, but now not as bad as before. the noise is more like a buzz now instead of a louder rattling noise. can anyone tell me what else to do to get rid of the noise. thank you guys.....

 

Check the heat shields around the intermediate pipe, exhaust manifold and head pipe.

 

one of the heat sheilds is loose, rip that focker off

 

The 2k buzz is a common problem, there is a service bulletin that calls out for new springs, bolts and gaskets on the intermediate exhaust pipe.