335i Start Up Rattle in Rear Drivers-Side Exhaust... Normal? - BMW 3-Series Forum (F30 / F32)

martinf79 · 11-10-2012, 12:55 PM

Yesterday, I started my car w/ the door still opened, and I heard for the first time (assuming, because the door was open) a rattle coming from the drivers-side rear exhaust. I had someone listen to see where it was coming from, and it appears to be the damper inside the exhaust (which closes on start up), but seems as though it is rattling inside the exhaust as it closes. The rattle is only for a second and stops, but doesn't sound very good.

Can others w/ a 335 try starting their car (w/ the door open) and listen to see if their cars are making this noise as well. Trying to figure out if that's just the way the car is, or whether I have something loose (fyi - I don't hear anything when starting the car in the cabin w/ the doors closed).

Would appreciate perspectives.

Carnook · 11-10-2012, 01:06 PM

Yes I have this. I think it's normal.

shivaswrath · 11-10-2012, 01:10 PM

Right side exhaust is the only one open when you first start up...at least for me, on a cold day.

martinf79 · 11-10-2012, 01:10 PM

Quote:

Originally Posted by Carnook

Yes I have this. I think it's normal.

Great - thanks. Sounds like an old muffler ... wish they could have designed this differently. Doesn't sound great.

martinf79 · 11-10-2012, 01:29 PM

Quote:

Originally Posted by shivaswrath

Right side exhaust is the only one open when you first start up...at least for me, on a cold day.

Yes - only right one is open. The left one is closed on start-up (for first 20 seconds or so). The damper on the left (which closes on start-up) is the one that makes a rattling sound. Do you have this too?

shivaswrath · 11-10-2012, 02:59 PM

Quote:

Originally Posted by martinf79

Yes - only right one is open. The left one is closed on start-up (for first 20 seconds or so). The damper on the left (which closes on start-up) is the one that makes a rattling sound. Do you have this too?

I have the M sport exhaust, so never had this problem. Sounds annoying though...

Carnook · 11-10-2012, 03:17 PM

Quote:

Originally Posted by shivaswrath

I have the M sport exhaust, so never had this problem. Sounds annoying though...

It's personal preference. I kind of like it because its rough and a bit old school. Overall I wish the 335i sport had a bit more exhaust note so maybe that's why I like it. It sounds like a real car :-)

midnight express · 11-10-2012, 11:16 PM

just noticed it on mine last week, but goes away after a little. i think its just the exhaust gate closing.

11-10-2012, 12:55 PM	#1
martinf79 Lieutenant Drives: F30 335i M Sport Join Date: May 2012 Location: Toronto, Canada Posts: 597 iTrader: (0)	335i Start Up Rattle in Rear Drivers-Side Exhaust... Normal? Yesterday, I started my car w/ the door still opened, and I heard for the first time (assuming, because the door was open) a rattle coming from the drivers-side rear exhaust. I had someone listen to see where it was coming from, and it appears to be the damper inside the exhaust (which closes on start up), but seems as though it is rattling inside the exhaust as it closes. The rattle is only for a second and stops, but doesn't sound very good. Can others w/ a 335 try starting their car (w/ the door open) and listen to see if their cars are making this noise as well. Trying to figure out if that's just the way the car is, or whether I have something loose (fyi - I don't hear anything when starting the car in the cabin w/ the doors closed). Would appreciate perspectives. __________________ 2013 335i ///M-Sport \| MPPK ON ORDER \| AW \| BD Leather \| 19” M3 ZCP Wheels \| M-Sport Brakes \| Adaptive M-Suspension \| Variable Sport Steering \| Premium Package \| Enhanced Bluetooth \| Sirius \| BMW Apps \| Heads Up Display \| Speed Limit Info \| M Performance Grill \| Front/Rear Painted Reflectors \| Coded
	Tweet

11-10-2012, 01:10 PM	#3
shivaswrath Lieutenant Colonel Drives: 2012 335i Join Date: Apr 2008 Location: Norwalk CT Posts: 1,989 iTrader: (2)	Right side exhaust is the only one open when you first start up...at least for me, on a cold day. __________________ 2012 335i Mineral Gray M Performance Whore: PPK\|Exhaust\|Brakes\|Performance Suspension Struts & Springs\|Black Kidney Grilles\|CF Spoiler and Mirror Caps\|M Sport 400M\|BMWF30.com 335i brakes FS!

11-10-2012, 11:16 PM	#8
midnight express @bmwgram Drives: EBII F30 335i 6MT Join Date: Aug 2012 Location: South Florida Posts: 472 iTrader: (1)	just noticed it on mine last week, but goes away after a little. i think its just the exhaust gate closing. __________________ Sold: 2012 F30 335i / 8AT / 1M Bumper / Slek Splitter / GT Haus exhaust / H&R springs / MORR Wheels Current: EBII F30 335i / 6MT / M-Sport Check out @bmwgram on instagram!

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

11-10-2012, 01:06 PM	#2
Carnook Private First Class Drives: BMW 2012 F30 335i Join Date: Feb 2012 Location: Canada Posts: 175 iTrader: (0)	Yes I have this. I think it's normal.