BOV sound changed

Vulcan50 · 11-09-2019, 12:36 AM

So initially after completing my FBO including hotside intake there was audible turbo whine, and a nice sharp BOV release. Now out of nowhere the whine has been replaced (or at least covered) by a lower pitch constant "whoosh." And where there used to be a sharp (quick, highish pitch) BOV release, it now has a low full "whoosh." Followed by( and partially overlapped by) the normal BOV release.

Something is clearly off and I don't know where to start since it won't build boost when it's not under load. So I can't hear it while I'm under the hood.

relative4 · 11-09-2019, 07:36 AM

Smoke test, BOV bench test

Vulcan50 · 11-09-2019, 09:20 PM

What would lead to sudden leaks?

slowgan · 11-12-2019, 11:57 AM

Check charge pipe and intercooler connections

b92 · 11-12-2019, 12:10 PM

Are you pulling any codes?

Jeff@TopGearSolutions · 11-12-2019, 02:37 PM

Hard to say, have you replaced all vacuum lines yet?

Vulcan50 · 11-13-2019, 12:31 AM

Quote:

Originally Posted by slowgan

Check charge pipe and intercooler connections

Will do, I'll likely be pulling the bumper soon anyway

Quote:

Originally Posted by b92

Are you pulling any codes?

Nothing showing a CEL. But I'll grab a history when I have time in the next day or so

Quote:

Originally Posted by Jeff@TopGearSolutions

Hard to say, have you replaced all vacuum lines yet?

Yes.

11-09-2019, 12:36 AM	#1
Vulcan50 Captain 433 Rep 780 Posts Drives: e92 335i Join Date: Mar 2017 Location: Peoria, IL iTrader: (0)	BOV sound changed So initially after completing my FBO including hotside intake there was audible turbo whine, and a nice sharp BOV release. Now out of nowhere the whine has been replaced (or at least covered) by a lower pitch constant "whoosh." And where there used to be a sharp (quick, highish pitch) BOV release, it now has a low full "whoosh." Followed by( and partially overlapped by) the normal BOV release. Something is clearly off and I don't know where to start since it won't build boost when it's not under load. So I can't hear it while I'm under the hood.
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11-09-2019, 07:36 AM	#2
relative4 Major 611 Rep 1,272 Posts Drives: '08 335xi E90 MT stage 1+ Join Date: Feb 2019 Location: Denver, CO iTrader: (0)	Smoke test, BOV bench test
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11-09-2019, 09:20 PM	#3
Vulcan50 Captain 433 Rep 780 Posts Drives: e92 335i Join Date: Mar 2017 Location: Peoria, IL iTrader: (0)	What would lead to sudden leaks?
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11-12-2019, 11:57 AM	#4
slowgan Enlisted Member 9 Rep 38 Posts Drives: 2008 335xi Coupe Join Date: Apr 2018 Location: Lincoln, NE iTrader: (0) Garage List 2008 335xi [0.00]	Check charge pipe and intercooler connections
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11-12-2019, 12:10 PM	#5
b92 Major 540 Rep 1,040 Posts Drives: E92 335is, 6MT Join Date: Feb 2016 Location: Rhode Island iTrader: (2)	Are you pulling any codes? __________________ 2011 E92 335is, Space Grey/Coral Red, 6MT. RB 2+, Wedge tuned. E85 PI coming soon.
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11-12-2019, 02:37 PM	#6
Jeff@TopGearSolutions 3441 Rep 79,211 Posts Drives: C6 Z06, 09 335i, 10 335xi Join Date: Dec 2008 Location: www.TopGearSolutions.com iTrader: (37)	Hard to say, have you replaced all vacuum lines yet?
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