XBimmers | BMW X1 Forum - View Single Post - Does anyone hear a whistle sound when letting off the gas? xDrive 35i

dicker · 08-30-2012, 08:13 PM

That's the bypass valve. Similar to a blowoff valve but it gets recirculated. If you tune the car you'll hear it more

08-30-2012, 08:13 PM	#3
dicker Captain 69 Rep 847 Posts Drives: F80 6MT Join Date: Apr 2008 Location: SoCal iTrader: (8)	That's the bypass valve. Similar to a blowoff valve but it gets recirculated. If you tune the car you'll hear it more
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