Exhaust noises...

[four]

I have a 95 240 and Im havin problems with an exhaust noise. &nbsp;It sounds like a rattling sound everytime i press on the gas. &nbsp;I took it to the shop and they said that I have to change the exhaust pipes from &nbsp;the cat-back. &nbsp;So i got me an HKS Hiper. &nbsp;Noise still didn't go away. &nbsp;I put my car up on a lift and listend. &nbsp;I kind of heard the noise from the actual cat converter but im not sure if thats it. &nbsp;Is it possible that its comming from the cat>? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/blush.gif" border="0" valign="absmiddle" alt=':blush:'>

[HotRodGuy]

Not sure about the '95, but on my '91 the rattle wuz coming from the heat shield in front of the cat, between the manifold and the cat. Or it could be the shield on the cat itself. Crawl under thar again and hold one hand on the shield and beat on the pipe (behind the cat) with the other. If the rattle goes away then ya know what it is.

I took the heat shields off of the exhaust pipe, which is OK. But I wouldn't recommend takin' um off the cat. It git's pretty hot! Just try to bend um er sumpthin to stop the rattle. If that's not it, then maybe yer cat is coming apart inside.

Hope this helps! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/confused.gif" border="0" valign="absmiddle" alt='???'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>

[95SEowner]

I had the exhaust rattling problem with my 95 as well. I took the car to the local nissan dealership when I could not isolate the problem. They told me the catalytic converter was bad, which sounded kind of unlikely since the car has less than 50k on it, but the sound did seem to be coming from the vicinity of the visible cat. I wasn't about to pay for a NISSAN cat + labor, so I took the car home and ordered a Cat from random tech which according to their application guide, and a customer service rep of theirs, was supposed to fit up to a 1997 model car. I was reluctant to get the thing because I had read that the real cat was just below the manifold on 95 up cars, and the other one was hollow. I was quite disappointed to find out that it is indeed hollow on the inside. The cat I bought from random tech was not hollow, obviously, so I don't know why they claim that it fits a 95 car. even though it would physically fit in place of the fake one, by installing it you would just be adding a converter, not replacing it. Anyway, the hollow cat has two heat shields tack welded to the top and bottom on the INSIDE with a piece of insulation sandwiched between the shields and the inner wall of the casing. pull the phony cat off the car and look in the inlet and outlet with a flashlight. check to see if the welds have come loose on those two metal plates, and tap them with a screwdriver handle or something. I did that and I knew right away that was the sound I was hearing. it is like a tinny kind of rattle that almost sounds like an exhaust leak. I tack welded the shields back up on the inside through the in and out pipes and the car is now quieter than ever. that random tech cat I bought is PN 822530 and I think it's meant for a 94 down model ONLY. the catalytic converter gaskets that NAPA sells for a 95 240 are for the Phony cat as well which leads me to believe getting a real cat or anything related to it for a 95 up 240 must be next to impossible. sorry for long winded reply. it's my first post here. I wouldn't want to see you waste a bunch of money like I did.
take it easy...