Hey guys,

So finished up my headers and mid pipe installed. It has high flow cats. Now I have a rattle sound only during deceleration once I get into the 1500 rpms and in gear. If I depress the clutch while the noise is happening, it will go away. If I give it gas while noise is occurring, it will go away. No noise while idling. I have check and I don't think it's rubbing against the heat shield or anything else. Any ideas? I don't want to think the cats are going bad. But if they are, how can I test that?

 

Anyone?

 

Do you have dual mode mufflers? If so it could be the exhaust flaps rattling; otherwise check for the spring hangers rattling too.

 

What brand headers? After I had my Kooks headers and X-pipe installed on my Z06, there was a vibration/rattle that developed. It was the worst under low RPM, usually turning in one direction (can't recall which - left or right). Turned out that a small portion of the X-pipe was too close to the tunnel, and it touched under certain RPM's. They readjusted everything and she was just fine afer that. Check your clearances between your piping and tunnel all the way from front to back.

 

Problem is that the rattling is coming from the tunnel on the passenger side

 

Pfadt headers with high flow cats. I know they are tucked up really well. I'll check. The rattling is coming from the passenger side. Seems like from the footwell area by the radio almost or under the center console. I am gonna check that header maybe it's touching the starter or some insulation there. Only happens under load. If I Rev and let the rpms drop, no rattle, it stops when I brake or depress the clutch.

Do you happen to know how to check to see if my cats aren't the problem? I don't think so but one never knows

 

Anyone?

 

Videos of the Noise.. Can you guys please help me figure this out!!! :will y:

 

I have the same problem. Happened after a couple months after my long tube/borla exhaust install.

I figure some of the bolts came slightly loose. Haven't gotten under the car to check though.

Rattle ONLY happens after a drive when the car is nice and hot and when i'm moving slow, either backing up into a driveway etc, or parallel parking. When i'm letting off the clutch. It's annoying and embarassing when people are around.

Gonna check the axleback connections. It feels like it's coming right in the middle by the x-pipe.

 

Trust me. My noise isn't loose bolts or nuts. I have triple checked everything to make it as tight as possible..

 

only you can get under there and check clearances of everything. Run your hands around the pipes and make sure nothing is hitting or rubbing. Check to make sure all the bolts on the tunnel plate are tight too.

NONE of us on this forum are going to be able to tell you what is rubbing where.

 

Clearly No one will exactly tell me where it's hitting but maybe someone will be able to identify the noise if they have expitienced it before. It's just odd. I checked again all clearance and everything looks good. I don't think I'm hitting anything. I have triple checked. I'm gonna try to tape with insulation the parts that I think are close . Other than that, I don't know what else to check for as for the headers making the noise.

 

Did u get a chance to check? I am starting to conclude my noise is the cats rattling inside. Let me know if you find ur cause

 

JC , the previous poster just jogged my memory a bit ... did you check the clearance of the over the axle over ?

I know your car is a manual and has more room than mine in that area as I have an A6 but it is tight up there

just a thought

Dave

 

See posts above....try hitting things with a rubber hammer.

Besides broken/ rattling cats, maybe motor or trans mounts are needing replacement.
Engine torque moving the drive train and then your rattle occurs.
Also note sometimes one thinks a sound is coming from right front when it is really left rear....so don't limiting your vision/ inspection.

Good luck.

 

I will check those as well. this weekend I am going to re torque and re check again to see if this helps. right now I am running out of options. and might just live with a noise. it doesnt seem to affect performance. However, lately I have realize that it happens as the exhaust warms up. we shall see. with the music I cant hear it but I bet its audible from other cars on the road if we are driving slow. oh well...

Now i need to get my tune done thou. I dont think that its shaking the exhaust cuz i dont feel any vibration

 

I am going to check again and again. This is true about the noises. It is just seems so much strong and coming where i assume the transmission sits in the tunnel but on the passenger side.

 

I thought the cat was rattling, it was the O2 sens, it was loose one turn..... fixed 3 years ago

 

I have mine plugged thou. I wonder what torque they need to be at

 

So today I spend a couple of hrs checking everything. I found a place where one of the pipes was super close to the frame. It's like by the starter bylut on the frame side of the car. Same level. Unbolted the headers and the mid pipes played with them a little bit. Also hammer the car pipes and cats with a rubber mullet. Found some rattle. Apparently the springs that hold the pipes were making some small rattle. Lubed those up and actually wrapped them with high heat tape. Then bolted everything back up, the passenger side header was still quite close to the frame so I taped a piece of header wrap to the frame itself using high temp tape. Went our for a drive and the rattle and buzzing is not present. Woo hooo.. so either the spring that hold the mid pipes or the header touching the frame.

On a side note, while checking the headers to the block for leaks, I did find what it appears to be an air leak. But I don't think it's from the headers but the valve cover. Can my seal be bad? After I turn the car on, I can feel some knocking near the rear of the valve cover on the passenger side. However still no tune so. But I can also feel air leaking out. I put my finger and I can feel it. I know it's not the header because fingerprint down to the header and my nail gets hot. Fingerprint up to the valve cover and it gets hot. How can I verify I have a leak on my valve cover? I tightened the 4 bolts down but I didn't want to break them.

Ahhhh one solution, then another problem.... ahhhhh