Just started noticing that between 3-4k RPM on my gsr my cat is making this raddling noise. I have about 90K on it with all tune ups. Its been doing that more lately and im just wondering if its time for me to replace the stock cat or if its just some kind of shield thats hitting it. Anybody have any input

 

I know at one time, i had a terrible rattle from my cat area at 4k rpm............i went back and re-tightened the bolts on the cat and my problems went away...also, check your heat shields or remove them. If the problem continues, then replace the cat

 

Do you have a stock header? If so 90% chance thats the culprit. Of all my friends with Integras (5), each and every single one has had the downpipe start to rattle. At first I thought it was the cat just like yourself, but after swapping the header and keeping everything else it went away. On a couple of my friends cars we replaced the downpipe and it fixed the problem as well. The noise only occured between 3-4k rpm's. Hope this advice helps you.

 

i thought my cat was rattling too... then i thought the heat shield fell off...turns out a header bolt had snapped and was rattling, and i tore the mount out of my tranny (what i thought was the heat shield falling off).


good luck to u, hopefully it wont turn out the same!