Weird sound after install axle back exhaust ...

skate0518 · 01-04-2011, 02:27 AM

Just weld an axle back exhaust onto my e92 N55 Lci But when driving speed over 20 miles, it start making a high pitch static noise. I can't figure out what is causing this sound. Anybody know what could be the problem & any way to fix ?

Bodie217 · 01-04-2011, 12:21 PM

can you post a video or sound clip?

Only thing that comes to mind is a shotty weld causing turbulence or an exhaust leak.

I'd also say it could be packaging material inside the new exhaust piping, but I'd hope the installer would've checked the exhaust before installing

Forcefed3 · 01-04-2011, 12:36 PM

What kind? Post a video.

Kevin@AKMotorwerk · 01-04-2011, 12:42 PM

exhaust leak, loose clamp, or the exhaust is hitting something and vibrating against it

Forcefed3 · 01-04-2011, 12:44 PM

Quote:

Originally Posted by Kevin@AKMotorwerk

exhaust leak, loose clamp, or the exhaust is hitting something and vibrating against it

+1
Thats all it could be really.

skate0518 · 01-04-2011, 03:36 PM

THX guys , I think it might be exhaust leak ! I will go check it out and post video if i can.

skate0518 · 01-04-2011, 06:15 PM

Just back from shop, they said the exhaust is fine and the weld is fine too. They said our car doesn't come with quality x pipe & no resonators, which is bad and suggest me to custom one .... but they have no idea what is causing the high pitch, like radio frequency type of annoying noise(the tone will vary depend on speed). Now after driving for 15 mins, i am having serious headache. That noise is killing me .... Where should i go and have some real "pro" to check out for me ?

NiVeDh · 01-04-2011, 09:01 PM

Check to make sure the exhaust isn't rubbing on anything, like the heat shielding material.

skate0518 · 01-04-2011, 09:15 PM

Checked ... nth is rubbing or ticking ... only when rev up, it comes on ! won't notice it when stationary. Geez .... hope back to stock is not the "only" way ...

Bodie217 · 01-05-2011, 12:05 AM

What axle back exhaust did you install?

Very shocking that the exhaust shop who did the work couldn't figure out what was making the noise...

Posting a video will help a lot.

Bodie217 · 01-05-2011, 12:09 AM

Does the high pitch noise sound like this?

skate0518 · 01-05-2011, 05:22 AM

no I am sure its not Turbo making that sound, its like the air flow that is causing it because when i hit it over 5k rpm, it actually went away but once the rpm drop around 2k-4k it comes up .... I will try video it TMR but not sure if camera can capture it.

skate0518 · 01-05-2011, 07:33 PM

from 00:34 to the end that noise is clearly there ...

01-04-2011, 02:27 AM	#1
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	Weird sound after install axle back exhaust ... Just weld an axle back exhaust onto my e92 N55 Lci But when driving speed over 20 miles, it start making a high pitch static noise. I can't figure out what is causing this sound. Anybody know what could be the problem & any way to fix ?
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01-04-2011, 12:21 PM	#2
Bodie217 Second Lieutenant 96 Rep 252 Posts Drives: '10 135i, '14 WRX, '14 Sequoia Join Date: Dec 2008 Location: Denver, CO iTrader: (1)	can you post a video or sound clip? Only thing that comes to mind is a shotty weld causing turbulence or an exhaust leak. I'd also say it could be packaging material inside the new exhaust piping, but I'd hope the installer would've checked the exhaust before installing __________________ -2010 BMW 135i - Titanium Silver - Procede v3/ETS 5" IC/AR Catless DP>N54mid>Berk Race/BMS OCC/VRSF Turbo Inlets & CP/SP rotors/Pagid RS29/APEX ARC8/Ohlins DFV/M3 Full Suspension and Bushings/Wavetrac LSD // 395rwhp/469rwtq on 91oct -2014 Toyota Sequoia Platinum - Overlander
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01-04-2011, 12:36 PM	#3
Forcefed3 Banned 131 Rep 4,732 Posts Drives: 2008 335i Join Date: May 2010 Location: South iTrader: (2) Garage List 2008 335i [1.00]	What kind? Post a video.
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01-04-2011, 12:42 PM	#4
Kevin@AKMotorwerk General 290 Rep 28,154 Posts Drives: THE GUY YOU LOVE TO HATE Join Date: Mar 2009 Location: hillsborough, nj iTrader: (1)	exhaust leak, loose clamp, or the exhaust is hitting something and vibrating against it
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01-04-2011, 03:36 PM	#6
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	THX guys , I think it might be exhaust leak ! I will go check it out and post video if i can.
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01-04-2011, 06:15 PM	#7
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	Just back from shop, they said the exhaust is fine and the weld is fine too. They said our car doesn't come with quality x pipe & no resonators, which is bad and suggest me to custom one .... but they have no idea what is causing the high pitch, like radio frequency type of annoying noise(the tone will vary depend on speed). Now after driving for 15 mins, i am having serious headache. That noise is killing me .... Where should i go and have some real "pro" to check out for me ? Last edited by skate0518; 01-04-2011 at 06:23 PM..
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01-04-2011, 09:01 PM	#8
NiVeDh Major General 426 Rep 8,003 Posts Drives: '08 E90 335i, '99 E36 M3 Join Date: Apr 2009 Location: Houston, TX & Atlanta, GA iTrader: (132) Garage List 2008 BMW 335i Sedan [8.66]	Check to make sure the exhaust isn't rubbing on anything, like the heat shielding material.
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01-04-2011, 09:15 PM	#9
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	Checked ... nth is rubbing or ticking ... only when rev up, it comes on ! won't notice it when stationary. Geez .... hope back to stock is not the "only" way ...
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01-05-2011, 12:05 AM	#10
Bodie217 Second Lieutenant 96 Rep 252 Posts Drives: '10 135i, '14 WRX, '14 Sequoia Join Date: Dec 2008 Location: Denver, CO iTrader: (1)	What axle back exhaust did you install? Very shocking that the exhaust shop who did the work couldn't figure out what was making the noise... Posting a video will help a lot. __________________ -2010 BMW 135i - Titanium Silver - Procede v3/ETS 5" IC/AR Catless DP>N54mid>Berk Race/BMS OCC/VRSF Turbo Inlets & CP/SP rotors/Pagid RS29/APEX ARC8/Ohlins DFV/M3 Full Suspension and Bushings/Wavetrac LSD // 395rwhp/469rwtq on 91oct -2014 Toyota Sequoia Platinum - Overlander
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01-05-2011, 12:09 AM	#11
Bodie217 Second Lieutenant 96 Rep 252 Posts Drives: '10 135i, '14 WRX, '14 Sequoia Join Date: Dec 2008 Location: Denver, CO iTrader: (1)	Does the high pitch noise sound like this? __________________ -2010 BMW 135i - Titanium Silver - Procede v3/ETS 5" IC/AR Catless DP>N54mid>Berk Race/BMS OCC/VRSF Turbo Inlets & CP/SP rotors/Pagid RS29/APEX ARC8/Ohlins DFV/M3 Full Suspension and Bushings/Wavetrac LSD // 395rwhp/469rwtq on 91oct -2014 Toyota Sequoia Platinum - Overlander
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01-05-2011, 05:22 AM	#12
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	no I am sure its not Turbo making that sound, its like the air flow that is causing it because when i hit it over 5k rpm, it actually went away but once the rpm drop around 2k-4k it comes up .... I will try video it TMR but not sure if camera can capture it.
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01-05-2011, 07:33 PM	#13
skate0518 First Lieutenant 58 Rep 351 Posts Drives: E46-E85-E92-F82 Join Date: Feb 2010 Location: LA iTrader: (2)	from 00:34 to the end that noise is clearly there ...
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