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Odd Resonance Sound After Intake Install

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Montauk
#41
I experience something very similar. Happens in the same rpm range but for me it's a higher pitched air noise. It's not super noticeable but under the right driving conditions I hear it. Sounds as if air is whistling through weather seal, but the speeds are slow and no wind so I know it's not that. Don't recall the noise with stock.
 


Hijinx

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#42
If you do just have paper towels ghetto plugging the symposer, you also have a boost leak from not having a air tight seal. Your plugging a hole connected to a pipe inches before the throttle body....
This is incorrect. And I won't repeat myself as to why.

To be on topic, I too have the whistle/whir. Both with stock and Cobb intakes. I adore it.
 


OP
MMMTRBO
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Thread Starter #43
I have the sound on the stock box. It used to annoy me but now I seem to like it for some reason. I guess it grew on me.

Be careful with the PCV nipple as it should be a standard pipe thread which is tapered in order to seat/seal while tightening. Trying to bottom it out like a normal nut/bolt just leads to expansion of the material it's threaded into and can lead to cracks and an inability to seal over time.
I have the same sound with my FSWERKS intake, so sounds like no matter what intake you have its gonna make it, I thought it was just the sound of the intake sucking air, never bothered me
I don't seem to have this sound with my Mountune intake.

I do have another question for you that have the Cobb intake.
Will the cross pipe work with the stock intake?
I think the flow might be better then the OE pipe.




Dave
My FiST with the prototype COBB intake makes the exact same sound as the video above. In San Antonio they have these river boats and under one of the bridges are bats. I could hear them squeeking, but my dad couldn't. Maybe some people just don't notice it?

Ian
I experience something very similar. Happens in the same rpm range but for me it's a higher pitched air noise. It's not super noticeable but under the right driving conditions I hear it. Sounds as if air is whistling through weather seal, but the speeds are slow and no wind so I know it's not that. Don't recall the noise with stock.
This is incorrect. And I won't repeat myself as to why.

To be on topic, I too have the whistle/whir. Both with stock and Cobb intakes. I adore it.
Thank you for the input everyone. I think Ian could be on to something that due to the sound frequency some people just don't notice it. Loud exhausts, loud music, creaks, rattles and people who rarely drive at modest throttle could all be other reasons why it doesn't bother people. I'm going to continue looking into the root cause because I want to run an aftermarket intake and I dont want to hear this sound lol.
 


BoostBumps

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#44
Thank you for the input everyone. I think Ian could be on to something that due to the sound frequency some people just don't notice it. Loud exhausts, loud music, creaks, rattles and people who rarely drive at modest throttle could all be other reasons why it doesn't bother people. I'm going to continue looking into the root cause because I want to run an aftermarket intake and I dont want to hear this sound lol.
I know I've heard this high pitched whirling noise prior to deleting the symposer box from the system with the stock intake setup....But after everything I did that annoying sound is no longer present...And my exhaust system (particularly at the low an rpm range in question and during cruising) isn't that loud that it would negate or drown out the sounds previously heard...and this is with no music playing...And I doubt my hearing has changed in the relatively short period of time ;).... Sorry, at the moment I can't recall what I else I may have done to eliminate this noise?

Hey good luck and let us know what you find!!
 


OP
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Thread Starter #45
I know I've heard this high pitched whirling noise prior to deleting the symposer box from the system with the stock intake setup....But after everything I did that annoying sound is no longer present...And my exhaust system (particularly at the low an rpm range in question and during cruising) isn't that loud that it would negate or drown out the sounds previously heard...and this is with no music playing...And I doubt my hearing has changed in the relatively short period of time ;).... Sorry, at the moment I can't recall what I else I may have done to eliminate this noise?

Hey good luck and let us know what you find!!
Thank you! You've been a lot of help! It definitely seems like this issue is a bit of an anomaly and different for everyone.
 


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Modesto
#46
I'm experiencing the exact same sound with my Cobb intake. My dad was riding in the car a few days ago, and he actually couldn't hear anything.
 


D1JL

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#47
I would think that if this noise is caused by air rushing through the intake you should be able to make it happen just by revving the engine to the appropriate RPM with the car not moving.
I cannot do this because I don't hear it at all.
Maybe placing a folded towel over parts of the intake until the sound is deadened might help you find it.

I suspect it is coming from the cross pipe.
Maybe some foiled heat wrap (or stick on) will deaden the sound.
It can't hurt keeping the intake air cooler as it passes over the exhaust manifold and turbo as well.

Anyway just a thought.



Dave
 


JPGC

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#48
I can only hear it in mine with the radio off and I'm actually listening for it, so it's not annoying to me via the reason it kind of like it. To get the sound, I have to be barely pressing the gas pedal.
 


westcoaST

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#49
Sounds like flow induced vibration. If the frequency is high enough, us old guys would not hear it. Years of our cillia exposed to rock and roll. Daves ideas are really good about sound deadener. It should attenuate the sound. FYI I'm old, have the mountune intake, and don't hear anyrhing except my sweet exhaust.
 


Messages
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Location
Springfield
#50
Yup, I've got it on the stock intake. Wife can't hear it at all. I piled 3 other car guys here at work in and 2 couldn't hear it while the third heard it right on queue with me. It's weird but not particularly worrisome.
 


OP
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Thread Starter #51
Just wanted to add a bit more info from Ken at Mountune...meh I put the Cobb Intake back on and I'm learning to get used to it.

Hi Tom,

Yes we are aware of the noise. All four of our Fiesta STs including the car that is 100% stock do the same thing. Perhaps its the sound symposer , we are not sure.

If we come across anything, we will report back.

Cheers




Ken Anderson
President
mountune, LLC. (USA)
 


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Location
Olathe
#52
I get the same noise with the MP215 kit. I honestly don't remember hearing before but I could be wrong.....
 


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Auburn
#53
Sorry to bring back a dead thread, but I have noticed this since shortly after installing my 2JRacing catted downpipe, Cobb CAI, and Boomba sound symposer delete. My first idea was the symposer delete so I returned that to stock and it didn't help at all (so I put it back in). I also noticed the MAF sensor got really loose somehow on the Cobb CAI. Screwed it down tight, but that didn't help. Has anyone learned anything new here? Absolutely none of this sound before installing the Cobb intake, and it really gets quite loud and is very annoying. Will go back to the stock intake if I have to, because it didn't make this noise at all.
 


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Boucherville
#54
Getting the exact same sound with fswerks intake. I thought it is the aluminium tubing causing that sound [dunno]. I can't hear the resonance with stock intake but it's very loud with the fswerks
 


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Location
Auburn
#55
Getting the exact same sound with fswerks intake. I thought it is the aluminium tubing causing that sound [dunno]. I can't hear the resonance with stock intake but it's very loud with the fswerks
I read through the entire thread hoping someone had a fix :(
 


westcoaST

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#56
Chris, I have the exact same set-up you have (Catted 2JR, Bomba SSD), except I have the Mountune airbox, induction hose and drop in filter. No air resonance at all. Must be the Cobb CAI. I also covered the outside of my Mountune box with thermal pad to mitigate heat soak.
 


BoostBumps

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#57
I have the Cobb CAI installed but I can't say that I'm hearing the same sound that your describe...However, I did hear that whirling sound prior to deleting the symposer with stock intake.....

If you read through this entire thread you'll see that some folks reported hearing that whirling sound and that some don't regardless of intake installed (i.e Mountune, Cobb, FS Werks, stock etc)....weird...
 


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Location
Auburn
#58
I have the Cobb CAI installed but I can't say that I'm hearing the same sound that your describe...However, I did hear that whirling sound prior to deleting the symposer with stock intake.....

If you read through this entire thread you'll see that some folks reported hearing that whirling sound and that some don't regardless of intake installed (i.e Mountune, Cobb, FS Werks etc)....weird...
Yep, I read through the entire thread. Was running stock with only the panel filter and Accessport flashed to stage 1 map. No noises. A couple months ago I added 2JR catted downpipe, Cobb CAI, and sound symposer delete (among other things, which are irrelevant), and flashed to stage 3 OTS. Sound started shortly after. Re-installing the symposer didn't make a difference, so it has to be the Cobb CAI. I'm assuming like the OP, if I reinstall the stock intake, I won't hear the noise. I'm interested in trying your clamp suggestion above the airbox lid, however. Great idea!
 


dyn085

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#59
It absolutely doesn't have to be the Cobb CAI because many people experience it without having that part, and sine have the part and don't have the noise.

I have the resonance and I'm using the stock intake.
 


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Location
Auburn
#60
It absolutely doesn't have to be the Cobb CAI because many people experience it without having that part, and sine have the part and don't have the noise.

I have the resonance and I'm using the stock intake.
Sorry, I should have been more clear. MY noise has to be the Cobb intake, since it doesn't make the noise with the stock intake.
 




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