Rattling noise
#1
Rattling noise
I have a 13 c250 with 82xxx miles on it. I am exsperiencinf first thing a pulse in the pedal at low speeds I can feel almost like a wheel bearing or something related to the wheel but when I speed up it doesn’t go faster. When I reach about 35 it goes away. I also which is my main problem is when my vehicle is warm and under load at low speeds about 11mph and slightly press accelerator there is a rattling/sound in the engine compartment like a fan hitting something and if I hold the pedal there the sound stays. If I barely accelerate a little more it gets louder and faster. But if I excellerate the pedal quicker and farther down when I hear it the sound goes away. Usually happens when I am somewhere with speed bumps and I have to slow down to go over he bump and go to speed up without trying to go fast to the next bump. That’s the only time I exsperience it. And I live in a trailer park so everyday. Took to Mercedes’ dealership and they said they need to bill me for another five hours to just diagnose it. That they never heard before and think it’s in the top of the motor. When they say never heard it before or seen it immediately I won’t have them work on it. If someone is going to guess and replace stuff I can do that. Thank you
Last edited by Dbradley2; 04-02-2022 at 02:29 AM.
#2
MBWorld Fanatic!
Here are my guesses based on experiences over time.
These could be 2 separate problems or both could be related.
The pulsating in the gas pedal may be a failing transmission mount or engine mount.
The low speed rattling may be an exhaust system part that has come loose from the daily driving over speed bumps.
OR
The low speed rattling could be something rotating that now touches part of the underbody or engine compartment because of misalignment due to a bad engine mount.
Dealer sevice is very expensive for this kind of thing on a 9-10 year old car. An independent shop could be much less expensive and more willing to work through this.
These could be 2 separate problems or both could be related.
The pulsating in the gas pedal may be a failing transmission mount or engine mount.
The low speed rattling may be an exhaust system part that has come loose from the daily driving over speed bumps.
OR
The low speed rattling could be something rotating that now touches part of the underbody or engine compartment because of misalignment due to a bad engine mount.
Dealer sevice is very expensive for this kind of thing on a 9-10 year old car. An independent shop could be much less expensive and more willing to work through this.
#3
The thing these said it needed at Mercedes’ cause I paid for safety inspection they tried to say failing suspension problem with the sway links. So maybe that is the pulsing I am thinking. I am gonna fix it myself cause they quoted me close to 600 for sway links….. and they said a power steering line is leaking. So I am gonna fix those and I will tell you if it fixed anything. I will check out exhaust for rattling but it is literally sounds like a fan. And check the transmission mounts and engine mounts. After I will take video of the sound and see if I can attach it on here thank you for your time.
#4
Super Member
Here are my guesses based on experiences over time.
These could be 2 separate problems or both could be related.
The pulsating in the gas pedal may be a failing transmission mount or engine mount.
The low speed rattling may be an exhaust system part that has come loose from the daily driving over speed bumps.
OR
The low speed rattling could be something rotating that now touches part of the underbody or engine compartment because of misalignment due to a bad engine mount.
Dealer sevice is very expensive for this kind of thing on a 9-10 year old car. An independent shop could be much less expensive and more willing to work through this.
These could be 2 separate problems or both could be related.
The pulsating in the gas pedal may be a failing transmission mount or engine mount.
The low speed rattling may be an exhaust system part that has come loose from the daily driving over speed bumps.
OR
The low speed rattling could be something rotating that now touches part of the underbody or engine compartment because of misalignment due to a bad engine mount.
Dealer sevice is very expensive for this kind of thing on a 9-10 year old car. An independent shop could be much less expensive and more willing to work through this.
#5
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Are these accelerate-by-wire (drive-by-wire) cars? If the pedal was pulsating due to a bad transmission mount, wouldn't more than just the pedal shake?
You are using Premium gas, right?
What specifically is wrong with the sway bar links? Are they completely broken?
You are using Premium gas, right?
What specifically is wrong with the sway bar links? Are they completely broken?