Borla Exhaust

D Griff · 08-26-2019, 12:51 PM

Hello everyone.

I have a 2014 328i M Sport six speed. Long story short, I've really never loved this car, always wanted a three series but I've found it to be pretty boring. Thinking about what would make the car more engaging, for me it really came to sound, these cars are dead silent from the factory and wanting to make it more sporty, I purchased a Borla S-Type catback. Install was easy and it appears to be a well made piece. Cold start is extremely loud and sounds... well not good, but it's otherwise a nice exhaust. It's not super loud, no highway drone, but sounds great accelerating, just a deeper, more sporty rumble and offers some nice pops and burbles upon throttle lift.

Now, onto my issue/question: the car now has a nasty rattle inside while accelerating. At idle or freeway speeds, it's quiet and fine. Accelerating in any gear, even under relatively light throttle, I experience a massive buzz. It sounds like the exhaust is contacting the heat shield on the bottom of the car and vibrating, it seems like it's coming from in the cabin near the tunnel bump on the floor of the back seat. I've lifted the car up several times, everything is tight, nothing is close to rubbing, I've even rotated a bunch of the sections to move them further from the car. It seems like it's really just the resonance of the exhaust rattling the heat shields.

Anyone have any other ideas to try to reduce this? I am thinking of throwing in the towel, putting the stock system back on, and selling the car.

misguided_will · 08-27-2019, 09:34 PM

i reckon a good exhaust should would be able to sort you out.
i had a nasty rattle and vibration after a so called "tuner" installed my downpipe on my 435i. had an exhaust shop look it over and they found the "tuner" hadn't installed it properly. was making contact with some part of the car. so yes i think try a good exhaust shop and see. they might be an easy fix

D Griff · 08-28-2019, 10:31 AM

Quote:

Originally Posted by misguided_will

i reckon a good exhaust should would be able to sort you out.
i had a nasty rattle and vibration after a so called "tuner" installed my downpipe on my 435i. had an exhaust shop look it over and they found the "tuner" hadn't installed it properly. was making contact with some part of the car. so yes i think try a good exhaust shop and see. they might be an easy fix

Good thought, thanks man. I have searched all over for anywhere it could be loose or rubbing and don't see anything, but they would obviously have more experience in this.

D Griff · 08-30-2019, 11:00 AM

Based on some other threads, I think this parking brake retaining clip is my issue: https://f30.bimmerpost.com/forums/sh...7#post25197687

I'm going to order the part from ECS for $9 and fingers crossed it'll fix the issue.

Wires · 08-30-2019, 11:30 AM

You definitely have it rubbing on something. I'd suspect your center tunnel brace.

And yes, it sounds like the car is about to fly apart in a very bad way....

Infamous039 · 08-30-2019, 11:40 AM

I have the Borla Attack on my car and had a rattle which was coming from the mid-pipe touching the car where it bends over the brace. I re-adjusted the mid-pipe so that nothing was touching and made sure everything was tight. I have no further vibrations

D Griff · 08-30-2019, 12:09 PM

I actually took the brace off and went for a drive and it sounded exactly the same.

It sounds exactly like this guy's video from another thread:

RockBamson · 08-30-2019, 01:24 PM

I had the same issue, took it back same day of install to have it fixed. As others have said, it ended up being the mid-pipe vibrating in contact with the underbody. Once the car was on the lift, you could replicate the rattle by hand just shaking the exhaust pipe. The shop put an extra washer or two where the mid-pipe brace connects to the underbody to create more space. No issue after that.

D Griff · 08-30-2019, 02:17 PM

Quote:

Originally Posted by RockBamson

I had the same issue, took it back same day of install to have it fixed. As others have said, it ended up being the mid-pipe vibrating in contact with the underbody. Once the car was on the lift, you could replicate the rattle by hand just shaking the exhaust pipe. The shop put an extra washer or two where the mid-pipe brace connects to the underbody to create more space. No issue after that.

Thanks. Did it sound like the above video?

RockBamson · 08-30-2019, 04:13 PM

Quote:

Originally Posted by D Griff

Thanks. Did it sound like the above video?

It did. Mine was most prominent on cold start up but also heard it like the video on acceleration.

neonnblack · 08-31-2019, 02:27 AM

My 340 has the same sound since messing with the exhaust. I'll have to look into both options here.

D Griff · 09-15-2019, 12:38 PM

Well... it was the parking brake clip, I'm really glad I found that other thread.

The replacement was kind of a bitch, have to lower the exhaust, remove the heat shield, loosen the gas tank down to the driveshaft to remove it. The new clip was still plastic and flimsy... I reinforced with some zip ties, hopefully it doesn't break again, but so glad to have it resolved!

I also replaced the spark plugs yesterday and seem to have eliminated a misfire code. That job was easy fortunately!

floridaorange · 09-15-2019, 01:49 PM

I could tolerate that for about 10 seconds - then it would be straight back to the shop that installed it.

neonnblack · 09-15-2019, 08:22 PM

Quote:

Originally Posted by D Griff

Well... it was the parking brake clip, I'm really glad I found that other thread.

The replacement was kind of a bitch, have to lower the exhaust, remove the heat shield, loosen the gas tank down to the driveshaft to remove it. The new clip was still plastic and flimsy... I reinforced with some zip ties, hopefully it doesn't break again, but so glad to have it resolved!

I also replaced the spark plugs yesterday and seem to have eliminated a misfire code. That job was easy fortunately!

One day I'll get around to mine also.

D Griff · 09-16-2019, 08:03 AM

Quote:

Originally Posted by floridaorange

I could tolerate that for about 10 seconds - then it would be straight back to the shop that installed it.

Haha well the shop that installed it was my yard... and turns out it had absolutely nothing to do with the exhaust... could've been the resonance was the straw that broke the camel's back on the e-brake hanger, but really it's just a turd design by BMW. It's all good now though, so I'm happy.

The car is certainly way more fun with the exhaust than its previous silent state.

floridaorange · 09-16-2019, 01:03 PM

Turd design?

D Griff · 09-16-2019, 04:50 PM

Quote:

Originally Posted by D Griff

Haha well the shop that installed it was my yard... and turns out it had absolutely nothing to do with the exhaust... could've been the resonance was the straw that broke the camel's back on the e-brake hanger, but really it's just a turd design by BMW. It's all good now though, so I'm happy.

The car is certainly way more fun with the exhaust than its previous silent state.

The parking brake cable clip... it's flimsy plastic and there's a lot of tension on it, bound to break at some point in the car's life and really annoying to replace because it's held on by a stud that also supports the gas tank. Funny because in most cases this car is actually really well designed from the ease of working on it standpoint.

neonnblack · 09-19-2019, 10:12 AM

Quote:

Originally Posted by D Griff

Quote:

Originally Posted by D Griff

Haha well the shop that installed it was my yard... and turns out it had absolutely nothing to do with the exhaust... could've been the resonance was the straw that broke the camel's back on the e-brake hanger, but really it's just a turd design by BMW. It's all good now though, so I'm happy.

The car is certainly way more fun with the exhaust than its previous silent state.

The parking brake cable clip... it's flimsy plastic and there's a lot of tension on it, bound to break at some point in the car's life and really annoying to replace because it's held on by a stud that also supports the gas tank. Funny because in most cases this car is actually really well designed from the ease of working on it standpoint.

This is the correct clip, right? That's the one that came from your link to the other post. Thanks.

D Griff · 09-19-2019, 11:45 AM

Quote:

Originally Posted by neonnblack

This is the correct clip, right? That's the one that came from your link to the other post. Thanks.

Yep, that's the one. That nut in the center of it that holds it on is threaded onto a stud that also holds up the center of the gas tank, then it slides on... pretty self explanatory once you have the part and are in there... but kind of a pain.

neonnblack · 09-19-2019, 12:07 PM

Quote:

Originally Posted by D Griff

Quote:

Originally Posted by neonnblack

This is the correct clip, right? That's the one that came from your link to the other post. Thanks.

Yep, that's the one. That nut in the center of it that holds it on is threaded onto a stud that also holds up the center of the gas tank, then it slides on... pretty self explanatory once you have the part and are in there... but kind of a pain.

Awesome thanks. One of those time consuming but low technical difficulty. Sounds like a bmw thing to me. Haha.

neonnblack · 10-02-2019, 11:23 PM

Boy that was a pain in the ass. Glad it's done though and quiet again.

I also took a picture just in case anyone comes across this post looking for more details. The red circle breaks, letting the two green circles (driveshaft and bowden cables) to touch while driving.

08-26-2019, 12:51 PM	#1
D Griff Enlisted Member 15 Rep 36 Posts Drives: 2014 328i, 2003 Corvette Join Date: Mar 2019 Location: Charlotte, NC iTrader: (0)	Borla Exhaust - Death Rattle Hello everyone. I have a 2014 328i M Sport six speed. Long story short, I've really never loved this car, always wanted a three series but I've found it to be pretty boring. Thinking about what would make the car more engaging, for me it really came to sound, these cars are dead silent from the factory and wanting to make it more sporty, I purchased a Borla S-Type catback. Install was easy and it appears to be a well made piece. Cold start is extremely loud and sounds... well not good, but it's otherwise a nice exhaust. It's not super loud, no highway drone, but sounds great accelerating, just a deeper, more sporty rumble and offers some nice pops and burbles upon throttle lift. Now, onto my issue/question: the car now has a nasty rattle inside while accelerating. At idle or freeway speeds, it's quiet and fine. Accelerating in any gear, even under relatively light throttle, I experience a massive buzz. It sounds like the exhaust is contacting the heat shield on the bottom of the car and vibrating, it seems like it's coming from in the cabin near the tunnel bump on the floor of the back seat. I've lifted the car up several times, everything is tight, nothing is close to rubbing, I've even rotated a bunch of the sections to move them further from the car. It seems like it's really just the resonance of the exhaust rattling the heat shields. Anyone have any other ideas to try to reduce this? I am thinking of throwing in the towel, putting the stock system back on, and selling the car. __________________ 2014 328i M Sport Estoril Blue Six Speed - Daily 2003 Corvette 50 AE Six Speed - Track/Fun
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08-27-2019, 09:34 PM	#2
misguided_will Second Lieutenant 57 Rep 299 Posts Drives: 2018 BMW 340i M Sport Join Date: Jan 2009 Location: Sydney iTrader: (0)	i reckon a good exhaust should would be able to sort you out. i had a nasty rattle and vibration after a so called "tuner" installed my downpipe on my 435i. had an exhaust shop look it over and they found the "tuner" hadn't installed it properly. was making contact with some part of the car. so yes i think try a good exhaust shop and see. they might be an easy fix __________________ 2018 F30 BMW 340i M Sport Injen EVO intake, OEM 437m rims, Catted VRSF dp, Magnaflow catback, Activ8 piggyback, Pedalbox.
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08-30-2019, 11:00 AM	#4
D Griff Enlisted Member 15 Rep 36 Posts Drives: 2014 328i, 2003 Corvette Join Date: Mar 2019 Location: Charlotte, NC iTrader: (0)	Based on some other threads, I think this parking brake retaining clip is my issue: https://f30.bimmerpost.com/forums/sh...7#post25197687 I'm going to order the part from ECS for $9 and fingers crossed it'll fix the issue. __________________ 2014 328i M Sport Estoril Blue Six Speed - Daily 2003 Corvette 50 AE Six Speed - Track/Fun
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08-30-2019, 11:30 AM	#5
Wires Brigadier General 1646 Rep 4,876 Posts Drives: 2016 340i xDrive Join Date: Apr 2008 Location: Calgary iTrader: (0)	You definitely have it rubbing on something. I'd suspect your center tunnel brace. And yes, it sounds like the car is about to fly apart in a very bad way....
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08-30-2019, 11:40 AM	#6
Infamous039 Second Lieutenant 148 Rep 241 Posts Drives: 2015 X5 Xdrive35i M-Sport Join Date: Apr 2013 Location: New Jersey iTrader: (0)	I have the Borla Attack on my car and had a rattle which was coming from the mid-pipe touching the car where it bends over the brace. I re-adjusted the mid-pipe so that nothing was touching and made sure everything was tight. I have no further vibrations __________________ BMW F06 M6 GC (Fun Ride) BMW F15 M-Sport 35iXDrive (Family Ride) BMW F48 X1 (Wife's Ride) 96 Camry (Daily Ride)
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08-30-2019, 12:09 PM	#7
D Griff Enlisted Member 15 Rep 36 Posts Drives: 2014 328i, 2003 Corvette Join Date: Mar 2019 Location: Charlotte, NC iTrader: (0)	I actually took the brace off and went for a drive and it sounded exactly the same. It sounds exactly like this guy's video from another thread: __________________ 2014 328i M Sport Estoril Blue Six Speed - Daily 2003 Corvette 50 AE Six Speed - Track/Fun
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08-30-2019, 01:24 PM	#8
RockBamson Enlisted Member 9 Rep 33 Posts Drives: F30 335i MSport Join Date: Jul 2016 Location: Nashville, TN iTrader: (0)	I had the same issue, took it back same day of install to have it fixed. As others have said, it ended up being the mid-pipe vibrating in contact with the underbody. Once the car was on the lift, you could replicate the rattle by hand just shaking the exhaust pipe. The shop put an extra washer or two where the mid-pipe brace connects to the underbody to create more space. No issue after that.
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08-31-2019, 02:27 AM	#11
neonnblack First Lieutenant 139 Rep 302 Posts Drives: 335i 6MT/e46 330xi Join Date: Nov 2018 Location: Reno, NV iTrader: (0)	My 340 has the same sound since messing with the exhaust. I'll have to look into both options here.
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09-15-2019, 12:38 PM	#12
D Griff Enlisted Member 15 Rep 36 Posts Drives: 2014 328i, 2003 Corvette Join Date: Mar 2019 Location: Charlotte, NC iTrader: (0)	Well... it was the parking brake clip, I'm really glad I found that other thread. The replacement was kind of a bitch, have to lower the exhaust, remove the heat shield, loosen the gas tank down to the driveshaft to remove it. The new clip was still plastic and flimsy... I reinforced with some zip ties, hopefully it doesn't break again, but so glad to have it resolved! I also replaced the spark plugs yesterday and seem to have eliminated a misfire code. That job was easy fortunately! __________________ 2014 328i M Sport Estoril Blue Six Speed - Daily 2003 Corvette 50 AE Six Speed - Track/Fun
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10-02-2019, 11:23 PM	#21
neonnblack First Lieutenant 139 Rep 302 Posts Drives: 335i 6MT/e46 330xi Join Date: Nov 2018 Location: Reno, NV iTrader: (0)	Boy that was a pain in the ass. Glad it's done though and quiet again. I also took a picture just in case anyone comes across this post looking for more details. The red circle breaks, letting the two green circles (driveshaft and bowden cables) to touch while driving. Attached Images Last edited by neonnblack; 10-02-2019 at 11:38 PM..
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