new exhaust and downpipe rattle

335MF · 01-11-2011, 08:01 PM

i have a 2007 335i AT. Just got the HKS exhaust and AR catted downpipes

. It sounds great but when im at a stop sign there is a rattling sound that at times gets pretty loud and it sounds like it is coming from right between the front seats and to get it to stop i have to put it back to neutral

. Is this normal during the break in period? If not is there anything to do to prevent the rattle? thanks in advance

NiVeDh · 01-11-2011, 08:03 PM

Sounds like something is rubbing. With my Top Speed exhaust (HKS "replica"), I had that rattling sound and it was due to the exhaust vibrating against the flex plate that's held on by Torx bolts.

335MF · 01-11-2011, 08:05 PM

is it ok to remove the flex plate?

NiVeDh · 01-11-2011, 08:11 PM

Quote:

Originally Posted by 335MF

is it ok to remove the flex plate?

A few shims/washers gave me enough room between the flex plate and exhaust. I didn't feel comfortable removing it.

BerkTechnology · 01-11-2011, 08:55 PM

+1

You should keep it there and shim/adjust as necessary to stop the rattling.

335TWNTURBO · 01-11-2011, 09:18 PM

video and sound clip

cn555ic · 01-11-2011, 09:20 PM

Maybe its the downpipes hitting the heatshield...

01-11-2011, 08:01 PM	#1
335MF New Member 0 Rep 24 Posts Drives: 335i Join Date: Oct 2010 Location: Cali iTrader: (0)	new exhaust and downpipe rattle i have a 2007 335i AT. Just got the HKS exhaust and AR catted downpipes . It sounds great but when im at a stop sign there is a rattling sound that at times gets pretty loud and it sounds like it is coming from right between the front seats and to get it to stop i have to put it back to neutral . Is this normal during the break in period? If not is there anything to do to prevent the rattle? thanks in advance
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01-11-2011, 08:03 PM	#2
NiVeDh Major General 422 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]	Sounds like something is rubbing. With my Top Speed exhaust (HKS "replica"), I had that rattling sound and it was due to the exhaust vibrating against the flex plate that's held on by Torx bolts.
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01-11-2011, 08:05 PM	#3
335MF New Member 0 Rep 24 Posts Drives: 335i Join Date: Oct 2010 Location: Cali iTrader: (0)	is it ok to remove the flex plate?
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01-11-2011, 08:55 PM	#5
BerkTechnology Lieutenant Colonel 223 Rep 1,565 Posts Drives: Fast Join Date: May 2008 Location: Irvine, CA iTrader: (1)	+1 You should keep it there and shim/adjust as necessary to stop the rattling.
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01-11-2011, 09:18 PM	#6
335TWNTURBO Captain 54 Rep 740 Posts Drives: 07 335i Join Date: Jul 2009 Location: MARYLAND iTrader: (0)	video and sound clip
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01-11-2011, 09:20 PM	#7
cn555ic 442 Rep 18,331 Posts Drives: 335i Join Date: Jun 2007 Location: US iTrader: (6)	Maybe its the downpipes hitting the heatshield...
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