2013 GL450 WTF is this noise?
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GL450
2013 GL450 WTF is this noise?
Did anyone ever experienced this type of noise coming from under the hood? Engine is off (have been off for at least 30 min), engine fan is off, accessories are off, in effect NOTHING is on. Dealer doesn't know what it is either.
(Turn the sound up)
http://vid296.photobucket.com/albums...%20noise_2.mp4
(Turn the sound up)
http://vid296.photobucket.com/albums...%20noise_2.mp4
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GL450
Nope, it stopped after about 10 min. Could not replicate. No idea what under the hood could make this noise. It sounded like an electronic beeping, although it could have been made by escaping air or anything else releasing high pressure (all speculation). Funniest part, dealer has no clue what it could be either. 
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'13 GL350 Bluetec
Air/hydraulic bleed down, likely from the brake booster. Turbo engines usually have a system that provides vacuum or pressure for power brakes, but that pressure bleeds down when the car is off. Normal.
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GL450
. Since the dealer didn't know what it could be and there appears to be no ill side effects, I'll go with this unless someone comes up with a better one 
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gl450
Could be the auxiliary coolant pump (sometimes also called afterrun pump) - helps circulate coolant at low RPM and after the engine is off, if certain conditions are present.
Not sure where it is on this engine, but look for a cylinder with two coolant hose connections.
Not sure where it is on this engine, but look for a cylinder with two coolant hose connections.
