2009 C300. Hissing sound from engine? Please clarify for me!
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Joined: Jul 2010
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2009 C300 4Matic
2009 C300. Hissing sound from engine? Please clarify for me!
I went to the Benz Dealer yesterday to fix some problems.
One of them was a hissing sound from the engine.
When the engine is on and I'm driving, there is a hissing sound. It sounds as if I have a speaker on but without any music coming out of it.
When I hit the brakes, the hissing sound goes away. The harder I press on the brakes, the sound disappears. It sounds like I am "controlling the hissing volume" with the brakes. (If I press on the brakes really softly, the sound becomes really minimal.)
The service rep. said this is the sound of engine pumps running and that it is NORMAL.
When I got a 2010 C300 loaner car, it didn't have this sound...
So... anyone know if this is normal or a problem?
Thanks a lot for you guys' help!
One of them was a hissing sound from the engine.
When the engine is on and I'm driving, there is a hissing sound. It sounds as if I have a speaker on but without any music coming out of it.
When I hit the brakes, the hissing sound goes away. The harder I press on the brakes, the sound disappears. It sounds like I am "controlling the hissing volume" with the brakes. (If I press on the brakes really softly, the sound becomes really minimal.)
The service rep. said this is the sound of engine pumps running and that it is NORMAL.
When I got a 2010 C300 loaner car, it didn't have this sound...
So... anyone know if this is normal or a problem?
Thanks a lot for you guys' help!
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
I went to the Benz Dealer yesterday to fix some problems.
One of them was a hissing sound from the engine.
When the engine is on and I'm driving, there is a hissing sound. It sounds as if I have a speaker on but without any music coming out of it.
When I hit the brakes, the hissing sound goes away. The harder I press on the brakes, the sound disappears. It sounds like I am "controlling the hissing volume" with the brakes. (If I press on the brakes really softly, the sound becomes really minimal.)
The service rep. said this is the sound of engine pumps running and that it is NORMAL.
When I got a 2010 C300 loaner car, it didn't have this sound...
So... anyone know if this is normal or a problem?
Thanks a lot for you guys' help!
One of them was a hissing sound from the engine.
When the engine is on and I'm driving, there is a hissing sound. It sounds as if I have a speaker on but without any music coming out of it.
When I hit the brakes, the hissing sound goes away. The harder I press on the brakes, the sound disappears. It sounds like I am "controlling the hissing volume" with the brakes. (If I press on the brakes really softly, the sound becomes really minimal.)
The service rep. said this is the sound of engine pumps running and that it is NORMAL.
When I got a 2010 C300 loaner car, it didn't have this sound...
So... anyone know if this is normal or a problem?
Thanks a lot for you guys' help!
Talk to the Service Manager.
Member
Joined: Feb 2010
Posts: 86
Likes: 5
From: San Francisco
2005 E320 Base
Were you able to confirm that it is vacuum leak problem?
My 2 weeks "brand new" 2012 C250 Sedan also have a weird hissing sound coming from the engine when idle. Here is the sound clip recorded by my android phone:
http://yourlisten.com/channel/conten...n=8cjeoqorhrwg
Does anyone know what problem this may be? Does this sound like vacuum leak? Thanks!
My 2 weeks "brand new" 2012 C250 Sedan also have a weird hissing sound coming from the engine when idle. Here is the sound clip recorded by my android phone:
http://yourlisten.com/channel/conten...n=8cjeoqorhrwg
Does anyone know what problem this may be? Does this sound like vacuum leak? Thanks!
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
You may want to remind them that if you end up plowing your car into something because of your obvious vacuum leak, MB will be taking care of you for life...hate lawsuits and the threat of them but a reminder of this potentially being a saftey issue often does grease the wheels.
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MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Were you able to confirm that it is vacuum leak problem?
My 2 weeks "brand new" 2012 C250 Sedan also have a weird hissing sound coming from the engine when idle. Here is the sound clip recorded by my android phone:
http://yourlisten.com/channel/conten...n=8cjeoqorhrwg
Does anyone know what problem this may be? Does this sound like vacuum leak? Thanks!
My 2 weeks "brand new" 2012 C250 Sedan also have a weird hissing sound coming from the engine when idle. Here is the sound clip recorded by my android phone:
http://yourlisten.com/channel/conten...n=8cjeoqorhrwg
Does anyone know what problem this may be? Does this sound like vacuum leak? Thanks!
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MBWorld Fanatic!
Joined: Dec 2001
Posts: 3,430
Likes: 187
From: USA
W140 Mercedes S350, W221 S550 sport
I have a sound like this on a 2010 c300. It's like a hissing/static sound above 30 mph and gets louder the faster you go. It sounds like its coming from the middle of the dash area. Braking doesn't effect it and I even put it in neutral at 50 mph and shut the engine and radio off while coasting and it's still there. Ideas???
