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Discussion Starter · #1 ·
Need help from all you 8th experts out there! I have this sound that occurs at low rpms, and surely no doubt will happen at 1700 and 3000 rpms on deceleration. The first video is outside the car so I made an annotation pop up every time it occurs. Second video is inside the car so you can just see the needle drop near 3000 rpms and it occurs.

Any help or advice is appreciated!


 

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I listened to that a bunch of times, and hooked my laptop up to my big speakers and listened to it some more. About the only thing I can think of would be a loose or rattling part on the exhaust, or a rattling heat shield. It sounds like death on my laptop, but on my real speakers I can make out a stainless steel type rattle.

Since it also only happens at specific rev ranges and actions, it points me towards an exhaust rattle.

Have you checked out under your car yet? checked the springs on your exhaust flange? one of those rattling could sound pretty similar, but don't overlook any of them, something in the back can be transmitted up front. If you can't find anything thump your exhaust pipes under the car with the soft side of your fist to try and make the whole thing shake a bit.
 

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It's due to the natural resonance of the material. It'll vibrate at certain frequencies, so between 1700/3000 RPMs is the range for that frequency.

My FG2 was doing this a couple months ago as well for the record. Never had a chance to get under and look since the rattle disappeared after a bit. Lol. Always good to take a look as mentioned before though. It's most likely a piece of the exhaust, be it spring, heat shield, flange, etc.


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Discussion Starter · #6 ·
My god all you guys were right haha. It was a spring bolt not compressed all the way.

I just thought it was impossible to be an exhaust part because it only made a sound specifically at 1700, and 3000, not even in between.

Thank you guys! If you don't know, 8thcivic fuhggin knows.
 

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My god all you guys were right haha. It was a spring bolt not compressed all the way.

I just thought it was impossible to be an exhaust part because it only made a sound specifically at 1700, and 3000, not even in between.

Thank you guys! If you don't know, 8thcivic fuhggin knows.
Spring bolt? Like one from the stock axle back?

I have a sound similar to this ever since I've done my header install (kidd header that implements spring bolts on the test pipe). I'm wondering if that could be the culprit :think:

I've been under there a million times and nothing is hitting or even close to hitting
 

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Discussion Starter · #12 ·
Did yours make the sound too when shifting? Particularly under 4k.

I'm really wondering if my spring bolts are what's causing it also. I can't wait to get under there and see.
Mine only did it at 1700 and 3000 rpms, in gear and any gear 1-6 during deceleration. On acceleration there was no sound at all. I'm guessing on decel in gear you have more drone, which creates the perfect resonance that rattled my spring bolts at those rpms. Your rpms might be different but if it sounds the same, then its probably your header/exhaust.

Let's say I shift around 3500 and land under 3000, it wouldn't make the sound when the needle passes 3000 on its way down, because I'm out of gear (neutral) at that moment.

Sorry, super tired right now not sure if this made sense or sounds dumb. I'll check this tomorrow and make sure it makes sense lol! :corona: :beer: :sleep:
 

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Here's a quick video of my noise I took today. You can hear it pretty clearly from about 29-45 seconds.

My problem is more of an acceleration than a decel one. But I could see how it could happen either way. Every car/set up is slightly different.

I'll have it figured out this weekend.
 

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Well, my issue wasn't the spring bolts unfortunately. I took them off and replaced them with normal bolts and got the same noise as before.

My guess now is that it's the heat shield. Nothing is hitting the heat shield, but I'm thinking that at certain rpms it get it to vibrate just perfectly.

The never ending struggle...
 

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Discussion Starter · #19 ·
Did you hit your exhaust pretty hard? I had to hit really hard to replicate the sound. I hit the exhaust tip first, then the midpipe, then all the exhaust shields. I hope you find out man. I hate the sound of exhaust rattles, sounds so cheap and crappy. I should buy a rubber mallet or dead blow hammer. Would have saved the bottom of my fist from bruising lol.
 

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Did you hit your exhaust pretty hard? I had to hit really hard to replicate the sound. I hit the exhaust tip first, then the midpipe, then all the exhaust shields. I hope you find out man. I hate the sound of exhaust rattles, sounds so cheap and crappy. I should buy a rubber mallet or dead blow hammer. Would have saved the bottom of my fist from bruising lol.
I actually wasn't able to quite replicate the noise by hitting anything. I tried with a rubber mallet.

I need to replace my doughnut gasket, which is leaking a little. When I do that I'm going to mess with the heat shield and see if I can rig it so it won't move. I would like to remove it just to see, but I'm not sure if I can with the header still intact or not :think:

Thanks, I hope I do too. I agree, makes the car sound so cheap.
 
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