Hey so I just installed a new catback exhaust the other day. The exhaust however does not sit flush against the cat donut flange.

I noticed I get a metallic rattle when I blip the accelerator or about 1/4 throttle.

I then also noticed that it only happens when the car or exhaust is fully warmed up after maybe 10 minutes of driving.

I already checked against any possible rattles against heatshields and frames.


Anyone got any ideas or could it be related to that donut flange?

 

What series car do you have? What manufacturer is the exhaust? Do have the oem mid pipe or aftermarket? If aftermarket, what brand?

 

07 Model, Raceroots single-side catback. OEM Cat.

 

Is the cat back 2 pieces or one? Is there a chance you have something on upside down?

 

Catback has two pieces, the connecting pipe and the muffler. They should be correct as the hooks go straight to where the hangers sit.

 

i had the exact same set up as you a few months back. oem cat with race roots single sided exhaust. it was notorious for making a rattling sound. it also rattled when i stepped on the accelerator like you did. is your extension tip on? that separate piece with the titanium tip that came with the exhaust? i found out that when it makes a rattling sound, i'd put my foot on the tip (with my shoes on of course) and the sound would go away. if i'd take my foot off, it makes a rattle sound again. i'm guessing it was the tip being loose. i just learned to dealt with it. it has since been sold though. try holding the exhaust tip with your foot to see if the sound goes away and it is indeed where it is coming from.

ps. i'm not liable if you burn your feet lol

 

hmm i'll give it a try.

but I find it weird it only rattled when the car was fully warmed up and on the accelerator :S

 

What holds the tip on? Are there screws directly opposite each other 180* out? Ive seen that before on other cars. As the exhaust comes up to temp, the pipe will contract slightly and cause the tip to pivot like a see-saw on those two screws creating a rattle. Adding a 3rd screw at a 45* from those 2 will do the trick.