Clunking noise
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Clunking noise
I start the engine and the car starts to move...but I hear a clunking noise...what is that? it's just one clunking noise...just like a metal noise
Also when stopping at traffic light, I can feel a bit of vibration...down under
On a cold start, the vibration presents...is it normal...is that how it warms up?
Also when stopping at traffic light, I can feel a bit of vibration...down under
On a cold start, the vibration presents...is it normal...is that how it warms up?
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From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Hard to say as there are a lot of variables, but it sounds like it could be a motor mount issue. A few of us have experienced an engine "wobble" on cold starts. It seems like that particular issue goes away with a few thousand miles on the vehicle.
Last edited by C300Sport; Oct 19, 2008 at 06:50 AM.
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I wouldn't be too worried about it. My C 300 4 MATIC has the same "clunk" noise the moment you start to drive the car after a cold-start. My car "wobbles" on a cold-start too. It sounds like the car has a loose exhaust or loose manifold. I was told that those noises are normal.
I notice that the engine performs a lot better, smoother and quieter after the car has been driven for a long distance. The engine in our cars need to be ran at an optimum temperature and engine speed. I accelerate "hard" sometimes all the way to 3500rpm at each gear change. The engine sounds a lot better and smoother after a few of those "hard" accelerations.
My suggestion is to ignore all those "unexplainable" noises and just enjoy the car. Also, lower your expectation beacase at the end of the day, a Mercedes is still a car. But is is one with safety, engineering, and prestige
I notice that the engine performs a lot better, smoother and quieter after the car has been driven for a long distance. The engine in our cars need to be ran at an optimum temperature and engine speed. I accelerate "hard" sometimes all the way to 3500rpm at each gear change. The engine sounds a lot better and smoother after a few of those "hard" accelerations.
My suggestion is to ignore all those "unexplainable" noises and just enjoy the car. Also, lower your expectation beacase at the end of the day, a Mercedes is still a car. But is is one with safety, engineering, and prestige
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Actually, what I feel is that on a cold start off - the first 2-3 shift of the transmission is "rough" - not a rough shift, but the car is holding the RPMs higher before that first 2-3 shift then it normally does, it must be some kind of internal self check its performing?
I do not have any abnormal vibration, other then the increased vibration associated with increased RPMs at cold start, and the car trying to get the emissions system warmed up as soon as possible. That's normal.
I do not have any abnormal vibration, other then the increased vibration associated with increased RPMs at cold start, and the car trying to get the emissions system warmed up as soon as possible. That's normal.
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
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From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Actually, what I feel is that on a cold start off - the first 2-3 shift of the transmission is "rough" - not a rough shift, but the car is holding the RPMs higher before that first 2-3 shift then it normally does, it must be some kind of internal self check its performing?
I do not have any abnormal vibration, other then the increased vibration associated with increased RPMs at cold start, and the car trying to get the emissions system warmed up as soon as possible. That's normal.
I do not have any abnormal vibration, other then the increased vibration associated with increased RPMs at cold start, and the car trying to get the emissions system warmed up as soon as possible. That's normal.
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Joined: Jul 2007
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I wouldn't be too worried about it. My C 300 4 MATIC has the same "clunk" noise the moment you start to drive the car after a cold-start. My car "wobbles" on a cold-start too. It sounds like the car has a loose exhaust or loose manifold. I was told that those noises are normal.
I notice that the engine performs a lot better, smoother and quieter after the car has been driven for a long distance. The engine in our cars need to be ran at an optimum temperature and engine speed. I accelerate "hard" sometimes all the way to 3500rpm at each gear change. The engine sounds a lot better and smoother after a few of those "hard" accelerations.
My suggestion is to ignore all those "unexplainable" noises and just enjoy the car. Also, lower your expectation beacase at the end of the day, a Mercedes is still a car. But is is one with safety, engineering, and prestige
I notice that the engine performs a lot better, smoother and quieter after the car has been driven for a long distance. The engine in our cars need to be ran at an optimum temperature and engine speed. I accelerate "hard" sometimes all the way to 3500rpm at each gear change. The engine sounds a lot better and smoother after a few of those "hard" accelerations.
My suggestion is to ignore all those "unexplainable" noises and just enjoy the car. Also, lower your expectation beacase at the end of the day, a Mercedes is still a car. But is is one with safety, engineering, and prestige
I also noticed a rattling noise (you have to really listen to it) somewhere inside the front dash...it sounds like a noise from a piece of loose clock arrow or some sort
