Wastegate Rattle after resonators? (Video)

GODDSPD · 03-16-2016, 11:32 PM

Installed vibrant 1792 resonators in place of secondaries to my Bmw PE mod exhaust, and now have a rattle on low rpms as the rpms fall that sounds similar to wastegate rattle.

When I pulled the cats, one had a large hole blown out and other was literally completely empty (no honeycomb whatsoever) from 2step, so it's not like they were silencing anything.

Video-

Stock turbos but they are fairly new, and the sound was not there before the resonators were installed. I thought it might be something rubbing, but it seems quite a few n54s have this sound. Any thoughts?

nitehawk · 03-17-2016, 12:06 AM

Video is private...

GODDSPD · 03-17-2016, 12:38 AM

Quote:

Originally Posted by nitehawk

Video is private...

Edited first post. Thanks

Flex68 · 03-17-2016, 05:46 AM

Doesn't sound like waste gate more like fart sound due to blockage somewhere in the exhaust

GODDSPD · 03-17-2016, 11:08 AM

Quote:

Originally Posted by Flex68

Doesn't sound like waste gate more like fart sound due to blockage somewhere in the exhaust

I don't see how I could have created blockage by replacing cats with the straight through resonators, but I'll look into it.

Anyone else experiencing this sound?

mojobmw_e90 · 03-17-2016, 11:09 AM

U check the flapper on the exhaust and see if it's loose?

GODDSPD · 03-17-2016, 12:00 PM

Quote:

Originally Posted by mojobmw_e90

U check the flapper on the exhaust and see if it's loose?

No, I'll do that today. I didn't realize it could be loose. Is it as simple as tightening it down with a screwdriver/wrench?

msjt · 03-17-2016, 12:14 PM

Quote:

Originally Posted by GODDSPD

No, I'll do that today. I didn't realize it could be loose. Is it as simple as tightening it down with a screwdriver/wrench?

I thought PE exhaust doesn't have the flap?

GODDSPD · 03-17-2016, 01:03 PM

Quote:

Originally Posted by msjt

I thought PE exhaust doesn't have the flap?

Its actually a PE mod to the stock muffler, so the flapper is still in place. I should have been more clear in the OP.

GODDSPD · 03-17-2016, 01:23 PM

Update- got it on a lift and it's definitely not the flapper, but it's clearly coming from the drivers side muffler.

I'm guessing something is stuck in there. Possibly part of the cat or,worst case, the exhaust mod is failing.

I'm just going to drive a bit with some 2 step action to hopefully clear it out. If not I'll be cutting open the muffler again...

Thanks for the input.

03-16-2016, 11:32 PM	#1
GODDSPD Second Lieutenant 39 Rep 236 Posts Drives: 335i Join Date: Dec 2013 Location: Orange County iTrader: (2)	Wastegate Rattle after resonators? (Video) Installed vibrant 1792 resonators in place of secondaries to my Bmw PE mod exhaust, and now have a rattle on low rpms as the rpms fall that sounds similar to wastegate rattle. When I pulled the cats, one had a large hole blown out and other was literally completely empty (no honeycomb whatsoever) from 2step, so it's not like they were silencing anything. Video- Stock turbos but they are fairly new, and the sound was not there before the resonators were installed. I thought it might be something rubbing, but it seems quite a few n54s have this sound. Any thoughts? Last edited by GODDSPD; 03-17-2016 at 01:04 PM..
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03-17-2016, 12:06 AM	#2
nitehawk Lieutenant Colonel 107 Rep 1,909 Posts Drives: e92 335i 6MT Join Date: May 2011 Location: Toronto iTrader: (15) Garage List E92 BMW 335i [9.00] E92 BMW 335i \| Retired [10.00]	Video is private...
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03-17-2016, 05:46 AM	#4
Flex68 Captain 76 Rep 853 Posts Drives: E92 335i Join Date: Mar 2015 Location: Australia iTrader: (0)	Doesn't sound like waste gate more like fart sound due to blockage somewhere in the exhaust
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03-17-2016, 11:09 AM	#6
mojobmw_e90 Major 382 Rep 1,497 Posts Drives: 2014 E63S Join Date: Oct 2014 Location: Chicago IL iTrader: (3)	U check the flapper on the exhaust and see if it's loose?
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03-17-2016, 01:23 PM	#10
GODDSPD Second Lieutenant 39 Rep 236 Posts Drives: 335i Join Date: Dec 2013 Location: Orange County iTrader: (2)	Update- got it on a lift and it's definitely not the flapper, but it's clearly coming from the drivers side muffler. I'm guessing something is stuck in there. Possibly part of the cat or,worst case, the exhaust mod is failing. I'm just going to drive a bit with some 2 step action to hopefully clear it out. If not I'll be cutting open the muffler again... Thanks for the input.
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