Exhaust Noises after Downpipe / Frontpipe

swah_fk7

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So, over the weekend I installed a downpipe and frontpipe.

Now, at certain RPM's a loud metallic vibration noise resonates on the backside of my exhaust, like a drone, but it sounds like metal rattling / vibrating.
Is this the factory muffler can or the heat shield directly above it vibrating? It's driving me crazy, has anybody experienced anything like this? I'm considering removing my exhaust heat shield under the car by the trunk to see if it remedies the sound.
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So, over the weekend I installed a downpipe and frontpipe.

Now, at certain RPM's a loud metallic vibration noise resonates on the backside of my exhaust, like a drone, but it sounds like metal rattling / vibrating.
Is this the factory muffler can or the heat shield directly above it vibrating? It's driving me crazy, has anybody experienced anything like this? I'm considering removing my exhaust heat shield under the car by the trunk to see if it remedies the sound.
No, don't remove the heat shield. You are definitely going to get more sound, with a DP. Just to clarify, you kept the factory exhaust? You didn't modify it in anyway like remove the resonator? Also is this Catless?
 
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No, don't remove the heat shield. You are definitely going to get more sound, with a DP. Just to clarify, you kept the factory exhaust? You didn't modify it in anyway like remove the resonator? Also is this Catless?
It is a Catless Downpipe. Stock exhaust, car has 4600 miles.
It sounds like the vibration of the exhaust is causing the heat shield or the metal in the actual exhaust (The muffler pans) to resonate / vibrate.

EDIT; Seen similar setups, this sounds like an isolated issue which only I am experiencing. I wanted to experiment by taking off that rear trunk heat shield and see if that's what's causing the vibration. It's a metallic rattling sound. similar to how a brass instrument makes sound. The resonance of the metal is causing it to make a noise when under load (accelerating) and passing certain RPM's will make it drone for a second, and then quiet down as soon as the RPM passes the rpm the sound appears at.
 

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It is a Catless Downpipe. Stock exhaust, car has 4600 miles.
It sounds like the vibration of the exhaust is causing the heat shield or the metal in the actual exhaust (The muffler pans) to resonate / vibrate.

EDIT; Seen similar setups, this sounds like an isolated issue which only I am experiencing. I wanted to experiment by taking off that rear trunk heat shield and see if that's what's causing the vibration. It's a metallic rattling sound. similar to how a brass instrument makes sound. The resonance of the metal is causing it to make a noise when under load (accelerating) and passing certain RPM's will make it drone for a second, and then quiet down as soon as the RPM passes the rpm the sound appears at.
It could be something is loose, I assume you checked that all the bolts are tight and the hangers are fine. When I had my performance exhaust installed, it had to be re-tightened after a couple hundred miles. Also Catless you are going to have even more noise, but if it's a vibration sound, the pipe may be shaking (vibrating) because its loose somewhere. Check that the DP and FP are tight, the vibrations may be coming from the newly installed pipes
 
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It could be something is loose, I assume you checked that all the bolts are tight and the hangers are fine. When I had my performance exhaust installed, it had to be re-tightened after a couple hundred miles. Also Catless you are going to have even more noise, but if it's a vibration sound, the pipe may be shaking (vibrating) because its loose somewhere. Check that the DP and FP are tight, the vibrations may be coming from the newly installed pipes
It's not vibrating from under the car. The catless downpipe is secure. It's the sudden free-up of exhaust thats causing something metal by the trunk to rattle.
 


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I read that a catless down pipe and factory exhaust causes a wierd noise because the design of the tip. Not sure if this is true as I have a Catted down pipe
 
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I read that a catless down pipe and factory exhaust causes a wierd noise because the design of the tip. Not sure if this is true as I have a Catted down pipe
I removed both rear heat shields, remedied the problem a bit. It only resonates at a higher 4-5000 RPM now for an instant.
I'm going to see if changing tip fixes the issue. Or go full-retard and buy a catback e.e
 

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I removed both rear heat shields, remedied the problem a bit. It only resonates at a higher 4-5000 RPM now for an instant.
I'm going to see if changing tip fixes the issue. Or go full-retard and buy a catback e.e
Hey did you ever get this figured out? I think i'm having the same problem based on the way you described it. On my car i hear it if i reallly slowly let the RPMs build through the 4k-5k range. Sounds like a high pitch metallic virbration/clattering coming from the rear of the car.

I've got a catted PRL downpipe, prl front pipe and oem catback with all the parts still intact.
 

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The easiest way to figure this out is to have someone looking at it while you rev the engine.
 
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Hey did you ever get this figured out? I think i'm having the same problem based on the way you described it. On my car i hear it if i reallly slowly let the RPMs build through the 4k-5k range. Sounds like a high pitch metallic virbration/clattering coming from the rear of the car.

I've got a catted PRL downpipe, prl front pipe and oem catback with all the parts still intact.
Its the factory exhaust bro. Shit sucks.
 


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I just installed a catless 3" downpipe and frontpipe and I hear ? a rattle sound in neutral when I bring the rpms to about 1500 in neutral and let it decel kind of like a loose nut or bolt but when I installed it I double checked all the bolts and they were on there tight AF. Some told me it sounds like my waste gate chattering or something idk. You can hear it throughout the entire exhaust. It is only on deceleration once the rpms come down to about 1200 into idle
 

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I just installed a catless 3" downpipe and frontpipe and I hear ? a rattle sound in neutral when I bring the rpms to about 1500 in neutral and let it decel kind of like a loose nut or bolt but when I installed it I double checked all the bolts and they were on there tight AF. Some told me it sounds like my waste gate chattering or something idk. You can hear it throughout the entire exhaust. It is only on deceleration once the rpms come down to about 1200 into idle
I think this describes exactly what is happening to me....when you give it gas and let off throttle is sounds like a fidget spinner or something. I’m going to be inspecting the dp/fp area and see if there is any contact with a heat shield. I only did a dp install so I didn’t do much to the front pipe.

if you come up with any ideas let me know.
 

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I think this describes exactly what is happening to me....when you give it gas and let off throttle is sounds like a fidget spinner or something. I’m going to be inspecting the dp/fp area and see if there is any contact with a heat shield. I only did a dp install so I didn’t do much to the front pipe.

if you come up with any ideas let me know.
Will do, im putting her under the knife this afternoon.
 

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I had the same thing happening for a while, this is what I did to remedy it.

- Wrap the down-pipe and front-pipe in DEI (don't forget to get the stainless steel ties with it)
- For me, I was able to remove the stock exhaust side gasket (exhaust side, where front-pipe meets the exhuast)... My front pipe was made to work without that gasket since it comes with its own. The stock gasket in my case was redundant and rattling around causing the noises.
 

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I had the same thing happening for a while, this is what I did to remedy it.

- Wrap the down-pipe and front-pipe in DEI (don't forget to get the stainless steel ties with it)
- For me, I was able to remove the stock exhaust side gasket (exhaust side, where front-pipe meets the exhuast)... My front pipe was made to work without that gasket since it comes with its own. The stock gasket in my case was redundant and rattling around causing the noises.
Ok i look into that. My PLM downpipe and frontpipe came with all new gaskets including the turbo to downpipe gasket. Not sure if I was supposed to use the thin steel existing oem gasket or not but I didn't ? lol
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