C300 (Sports Sedan -2009)
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Joined: Jun 2020
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From: Southern California
C300 Sports Sedan
C300 (Sports Sedan -2009)
There's a whistling noise heard in the cabin (don't hear this outside or in the engine area). It comes on when the car is idling at a light. Generally, goes away when the car is accelerating. Usually don't hear the noise in the morning when the engine is cold. I started to notice the noise after a repair done recently; the brake vacuum pump was replaced. Not sure if this is related or not. Has anyone experienced this. If so, how do I fix this? Thanks, Kumar.
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Joined: Dec 2016
Posts: 797
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2018 C43
There's a whistling noise heard in the cabin (don't hear this outside or in the engine area). It comes on when the car is idling at a light. Generally, goes away when the car is accelerating. Usually don't hear the noise in the morning when the engine is cold. I started to notice the noise after a repair done recently; the brake vacuum pump was replaced. Not sure if this is related or not. Has anyone experienced this. If so, how do I fix this? Thanks, Kumar.
