Muffler rattle aftergolf tee mod

lance · 08-13-2007, 10:53 PM

Anybody else have this problem? After I did this mod I guess it's the resonator on the driver side, makes this rattling sound. I looked down there and it looks like a pressure piston valve thingy making the noise.

BoostedInPhx · 08-13-2007, 11:40 PM

Did you actually do the modification by removing the hose and then completely plugging the hose and cap the inlet to the diverter valve? If you did the other modification that inserts a ball bearing into the hose then reconnects the hose to the diverter valve it may make the diverter valve rattle. This happens because because the ball bearing has not sealed the hose completely and a small vaccum forms in the diaphram . This causes the valve to open partially and causes the rattle. I hope this helps.

lance · 08-15-2007, 09:28 PM

Quote:

Originally Posted by BoostedInPhx

Did you actually do the modification by removing the hose and then completely plugging the hose and cap the inlet to the diverter valve? If you did the other modification that inserts a ball bearing into the hose then reconnects the hose to the diverter valve it may make the diverter valve rattle. This happens because because the ball bearing has not sealed the hose completely and a small vaccum forms in the diaphram . This causes the valve to open partially and causes the rattle. I hope this helps.

I used an alan head screw that has no head that fit perfectly into the hose and was tight. I screwed it in about an inch just enough so it would fit back on the nipple. I know there is no way for that screw to be leaking as tight as it was.

Driver72 · 08-15-2007, 11:02 PM

I noticed the rattle a bit too.
I found it comes from the base of the valve under the exhaust pipe...that little metal "nipple" that sticks down.

I put a tiny bit of pressure on it with a rubber mallet and it stopped immediately.
I think it's because at low rpms that valve would usually be shut and therefore not rattle, but since it's been fooled to stay open at low rpms the idling occasionally causes it to rattle a bit.

So it'll be someone's project to figure out a way to keep that from occasionally rattling at idle.

lance · 08-16-2007, 09:33 AM

Rubber mallet?? Did you hit it?

Yeah,..it's kinda embarrasing. I actually had a guy come up to me in a convenience store the other day and ask me if that was my BMW out there. I said yes and he told me it was rattling and for me to have it looked at!

gonzo · 08-16-2007, 09:42 AM

Quote:

Originally Posted by lance

Rubber mallet?? Did you hit it?

Yeah,..it's kinda embarrasing. I actually had a guy come up to me in a convenience store the other day and ask me if that was my BMW out there. I said yes and he told me it was rattling and for me to have it looked at!

Did you tell him thanks? No rattles or 7-11 mechanics here.

Driver72 · 08-16-2007, 10:02 AM

Quote:

Originally Posted by lance

Rubber mallet?? Did you hit it?

No, since I knew the muffler was hot I knew I need something to touch it with.
Grabbed the rubber mallet out of my toolbox.
First thing I did was put a bit of pressure on that metal nipple thing on the bottom of the muffler right below the valve. It's basically the hinge that allows the valve to swing open and closed.
It stopped the rattling immediately.

Now to figure out a way to put pressure on it, or stop the rattling full time.

bimmerlex · 08-16-2007, 10:13 AM

I just disconnected that switch behind driver's tail light, and no rattling whatsoever, just a pleasant sound.

Driver72 · 08-16-2007, 10:46 AM

I don't think how you do the mod will make any difference.
If the valve is in the open position full time, there is the chance of a bit of rattle at times, as the hinge is swung open and therefore there is a bit of "slack" there and that's what's rattling.
You may not hear it in the car, I didn't either, but I was backing into my garage and got out of my car to make sure I was clear and that's when I noticed a slight rattling coming from the back.

Driver72 · 08-18-2007, 03:52 PM

Anybody try to silence the rattle with anything yet?
And did it work?

Orb · 08-26-2007, 01:56 AM

Quote:

Originally Posted by Driver72

Anybody try to silence the rattle with anything yet?
And did it work?

If you use screw to plug the hole then it will leak for sure at full vacuum. I know this for fact that your odds are very slim you get a full seal with a screw or flat surface.

The ball bearing is about as good as it gets. It will makes a perfect seal. When the exhaust heats up the pressure between the valve and bearing will oppose the any closing of the valve and should get rid of any rattle as it will pre load the flap with 2-5 PSI. Kind makes it better than the other options for the time being.

If there is an issue I see what I can come up with. I got no rattle of any type.

Orb

Driver72 · 08-26-2007, 11:59 PM

The screw I used is about 1/2 inch long and very square and very tight fit.
The rattle comes from the hinge on the top that runs down to the valve that allows it to open and close.

It rattles a bit because it stays in a fixed open position and doesn't have pressure on the hinge so it's a bit "loose."
Regardless of a ball bearing or screw, if the valve is opened FULLY all the time, there will be a bit of a rattle because the hinge/valve has play in it in the open position.

I solved the problem with a cotter like pin.

08-13-2007, 10:53 PM	#1
lance Second Lieutenant 22 Rep 269 Posts Drives: 09 335i Coupe Join Date: May 2006 Location: USA iTrader: (0)	Muffler rattle aftergolf tee mod Anybody else have this problem? After I did this mod I guess it's the resonator on the driver side, makes this rattling sound. I looked down there and it looks like a pressure piston valve thingy making the noise. __________________ 09 335i Space Gray
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08-13-2007, 11:40 PM	#2
BoostedInPhx Enlisted Member 0 Rep 44 Posts Drives: 335I Sedan Join Date: Feb 2007 Location: Phoenix, AZ iTrader: (0)	Did you actually do the modification by removing the hose and then completely plugging the hose and cap the inlet to the diverter valve? If you did the other modification that inserts a ball bearing into the hose then reconnects the hose to the diverter valve it may make the diverter valve rattle. This happens because because the ball bearing has not sealed the hose completely and a small vaccum forms in the diaphram . This causes the valve to open partially and causes the rattle. I hope this helps. __________________ Sparkling Graphite 335 Sedan, premium, black leather, sport, step, paddles and oil cooler Delivered 4/14/07
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08-15-2007, 11:02 PM	#4
Driver72 Brigadier General 351 Rep 4,484 Posts Drives: 335i - to new owners now. Join Date: Dec 2006 Location: California iTrader: (0)	I noticed the rattle a bit too. I found it comes from the base of the valve under the exhaust pipe...that little metal "nipple" that sticks down. I put a tiny bit of pressure on it with a rubber mallet and it stopped immediately. I think it's because at low rpms that valve would usually be shut and therefore not rattle, but since it's been fooled to stay open at low rpms the idling occasionally causes it to rattle a bit. So it'll be someone's project to figure out a way to keep that from occasionally rattling at idle.
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08-16-2007, 09:33 AM	#5
lance Second Lieutenant 22 Rep 269 Posts Drives: 09 335i Coupe Join Date: May 2006 Location: USA iTrader: (0)	Rubber mallet?? Did you hit it? Yeah,..it's kinda embarrasing. I actually had a guy come up to me in a convenience store the other day and ask me if that was my BMW out there. I said yes and he told me it was rattling and for me to have it looked at! __________________ 09 335i Space Gray
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08-16-2007, 10:13 AM	#8
bimmerlex Captain 73 Rep 885 Posts Drives: 2024 BMW X4M Competition Join Date: Jan 2007 Location: SoCal. iTrader: (25) Garage List 2025 BMW X5 40i M-S ... [9.75] 2024 BMW X4M Compet ... [0.00]	I just disconnected that switch behind driver's tail light, and no rattling whatsoever, just a pleasant sound. __________________ 2025 BMW X5 Xdrive40i M-Sport 2024 BMW X4M Competition
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08-16-2007, 10:46 AM	#9
Driver72 Brigadier General 351 Rep 4,484 Posts Drives: 335i - to new owners now. Join Date: Dec 2006 Location: California iTrader: (0)	I don't think how you do the mod will make any difference. If the valve is in the open position full time, there is the chance of a bit of rattle at times, as the hinge is swung open and therefore there is a bit of "slack" there and that's what's rattling. You may not hear it in the car, I didn't either, but I was backing into my garage and got out of my car to make sure I was clear and that's when I noticed a slight rattling coming from the back.
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08-18-2007, 03:52 PM	#10
Driver72 Brigadier General 351 Rep 4,484 Posts Drives: 335i - to new owners now. Join Date: Dec 2006 Location: California iTrader: (0)	Anybody try to silence the rattle with anything yet? And did it work?
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08-26-2007, 11:59 PM	#12
Driver72 Brigadier General 351 Rep 4,484 Posts Drives: 335i - to new owners now. Join Date: Dec 2006 Location: California iTrader: (0)	The screw I used is about 1/2 inch long and very square and very tight fit. The rattle comes from the hinge on the top that runs down to the valve that allows it to open and close. It rattles a bit because it stays in a fixed open position and doesn't have pressure on the hinge so it's a bit "loose." Regardless of a ball bearing or screw, if the valve is opened FULLY all the time, there will be a bit of a rattle because the hinge/valve has play in it in the open position. I solved the problem with a cotter like pin.
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