Has anyone figured out the thumping from the rear of the car? (03 C230k)
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Joined: Mar 2003
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From: Stamford, CT
2003 C230
Has anyone figured out the thumping from the rear of the car? (03 C230k)
Mine still does it after running it hard for a few minutes and then stopping with the engine idling at a light or something. Sounds really bad inside the car but it's almost inaudible outside the car.
CZ
CZ
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From: Bay Area, CA
My 230K sedan does the same thing, although it sounds more like "blooob blob blooob blooob blob". My vechicle makes this strange noise occasionally after it comes to a complete stop. I believe the sound is coming from the rear right area of the vehicle, probably somewhere below the right rear seat...
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Thread Starter
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Joined: Mar 2003
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From: Stamford, CT
2003 C230
John, can you be more specific as to where I can find the Purge valve service bulltn?
To be more specific the noise sounds something in between someone in the trunk hitting the back of the rear seat with their fists, or the muffler backfiring like "pop, pop, pop". It's definitely NOT gas sloshing around since it happens every time I run the car hard and then stop and idle regardless of amount of fuel in the tank. From the outside, the sound is very subdued more like tick, tock metallic sound and it seens to eminate from right infront the rear axle area. Inside the car the sound is amplified to a thump/pop.
After I stop and idle I hear it within a few seconds and I only get between 3 and 7 thumps/pops. After that it's quiet.
Sincerely
CZ
After I stop and idle I hear it within a few seconds and I only get between 3 and 7 thumps/pops. After that it's quiet.
Sincerely
CZ
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From: York, PA
2003 C230K Sport Coupe, 1986 190E 2.3
I have never had it happen. The only thumping I get is when I slide around a left hand corner and the rear sway seems to sound like it is rapping against something. Dealer could never find it and it only happens when I really am pushing it hard as I slide around a corner, it has to be a left, does not do it going right.
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From: The blue white rock, third out.
2002 C230 Coupe(M111)
Re: John, can you be more specific as to where I can find the Purge valve service bulltn?
Originally posted by czachari
To be more specific the noise sounds something in between someone in the trunk hitting the back of the rear seat with their fists, or the muffler backfiring like "pop, pop, pop". It's definitely NOT gas sloshing around since it happens every time I run the car hard and then stop and idle regardless of amount of fuel in the tank. From the outside, the sound is very subdued more like tick, tock metallic sound and it seens to eminate from right infront the rear axle area. Inside the car the sound is amplified to a thump/pop.
After I stop and idle I hear it within a few seconds and I only get between 3 and 7 thumps/pops. After that it's quiet.
Sincerely
CZ
To be more specific the noise sounds something in between someone in the trunk hitting the back of the rear seat with their fists, or the muffler backfiring like "pop, pop, pop". It's definitely NOT gas sloshing around since it happens every time I run the car hard and then stop and idle regardless of amount of fuel in the tank. From the outside, the sound is very subdued more like tick, tock metallic sound and it seens to eminate from right infront the rear axle area. Inside the car the sound is amplified to a thump/pop.
After I stop and idle I hear it within a few seconds and I only get between 3 and 7 thumps/pops. After that it's quiet.
Sincerely
CZ
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2003 C240 4matic
I have a 2003 240 4Matic and get a thumping sound "thump. thump, thump, from the trunk sometimes. Sounds as if there is someone in there trying to get out. 
I think some cars have two gas tanks that are connected. If so, and if my does, I wonder if it could be noise from the pump moving gas from one tank to another?
I think some cars have two gas tanks that are connected. If so, and if my does, I wonder if it could be noise from the pump moving gas from one tank to another?
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w203
'02 coupe
i have the same noise under the same conditions. thought it was the bose bass box in the rear and the HU noise volume adjust. But I unplugged the bass box and drove around for a few days but still heard it. I also found out that the trunk floor above the muffler gets warm after driving for awhile and then stooping (heat rises). maybe its the heat and material exspansion (rubbing) that is making the noise once stopped at a light.
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What sedans have the option of fold down rear sears? I have a 2004 c230k, and I was thumbing through the quick manual, and it has a picture of these two handles in the trunk, and I went to look, and it seems I don't have them :p
I haven't heard the thumping either.
I haven't heard the thumping either.
Thread Starter
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Joined: Mar 2003
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From: Stamford, CT
2003 C230
The floor idea sounds plausible
But this thump noise happens within a few seconds after stopping. Also, I don't think it happens if I stop and turn the ignition off. It only happens after I stop and idle....
Weird.
It's really embarassing when I have passengers. Even my 4 year old daughter is asking what's up with your car daddy?
CZ
Weird.
It's really embarassing when I have passengers. Even my 4 year old daughter is asking what's up with your car daddy?
CZ
