What is this sound?
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Joined: May 2021
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What is this sound?
The car has been making me nervous lately. In the past two months I got a low coolant warning which did turn out to be true. I topped off the coolant and everything has been good since. The tank has not lost coolant since and no obvious leaks anywhere so I am unsure where the coolant went. A few weeks ago, I got a low oil warning which was odd considering I had an oil change back in October. I pulled the dipstick and it looked fine and after some research I found that the sensor could go bad. The warning went away at the next restart and hasn't come back since. I don't believe that problems solve themselves so both of those live in the back of my brain almost every time I drive the car.
Now it is making this sound, I can't find an obvious source under the hood but its new. Is it a belt of some sort? I can't even see any belts under the hood so its hard to tell. I'd love to better describe the sound to you all but its a rhythmic sound that runs in time with the motor idling. The car has 57K on the odometer so my fear is that this is the new norm. Runs and drives beautifully as always.
The obvious answer is to take it to a mechanic which I will do but usually I have an idea of what I am in for before I go. This time, I am unsure.
Now it is making this sound, I can't find an obvious source under the hood but its new. Is it a belt of some sort? I can't even see any belts under the hood so its hard to tell. I'd love to better describe the sound to you all but its a rhythmic sound that runs in time with the motor idling. The car has 57K on the odometer so my fear is that this is the new norm. Runs and drives beautifully as always.
The obvious answer is to take it to a mechanic which I will do but usually I have an idea of what I am in for before I go. This time, I am unsure.
Senior Member
Joined: May 2015
Posts: 342
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From: Florida
GLE400, 2017 Porsche 911S
Definitely rhythmic like something is wrong with a belt or timing chain etc and the damaged(?) section is hitting the pulley(?) in rhythm to the engine rotation. Sorry for the very novice response!
Super Member
Joined: Dec 2019
Posts: 551
Likes: 133
From: Miami, Florida
W205 C63 AMG Coupe
Does the sound go away once the car is warmed up or does it stay no matter how long the car is running? It might be injector tick from the DI fuel injectors.
I had the low coolant warning as well with no obvious leaks or puddles under the car. I topped up the coolant with some distilled water and am keeping an eye on it, but it has yet to happen again. I suspect it might just be a bad cap on the coolant reservoir as there was some dried coolant on the expansion tank around the cap. I have ordered a new cap to eliminate that as a potential problem and would recommend that you check your cap as well.
I had the low coolant warning as well with no obvious leaks or puddles under the car. I topped up the coolant with some distilled water and am keeping an eye on it, but it has yet to happen again. I suspect it might just be a bad cap on the coolant reservoir as there was some dried coolant on the expansion tank around the cap. I have ordered a new cap to eliminate that as a potential problem and would recommend that you check your cap as well.
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Joined: May 2021
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Does the sound go away once the car is warmed up or does it stay no matter how long the car is running? It might be injector tick from the DI fuel injectors.
I had the low coolant warning as well with no obvious leaks or puddles under the car. I topped up the coolant with some distilled water and am keeping an eye on it, but it has yet to happen again. I suspect it might just be a bad cap on the coolant reservoir as there was some dried coolant on the expansion tank around the cap. I have ordered a new cap to eliminate that as a potential problem and would recommend that you check your cap as well.
I had the low coolant warning as well with no obvious leaks or puddles under the car. I topped up the coolant with some distilled water and am keeping an eye on it, but it has yet to happen again. I suspect it might just be a bad cap on the coolant reservoir as there was some dried coolant on the expansion tank around the cap. I have ordered a new cap to eliminate that as a potential problem and would recommend that you check your cap as well.
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Joined: Mar 2008
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C63s Cabriolet, BMW M4, Civic
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⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
Just your belts and pulleys mate. Even new ones will occasionally make the tropical bird sound if it's been a cold night or have a bit of moisture on them.
The sound we dread to hear is the cricket sound which is this.
When I had all my belts and pulleys refreshed it cost me $1200 AUD including labour etc.
The sound we dread to hear is the cricket sound which is this.
When I had all my belts and pulleys refreshed it cost me $1200 AUD including labour etc.
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Thread Starter
Junior Member
Joined: May 2021
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Just your belts and pulleys mate. Even new ones will occasionally make the tropical bird sound if it's been a cold night or have a bit of moisture on them.
The sound we dread to hear is the cricket sound which is this.
When I had all my belts and pulleys refreshed it cost me $1200 AUD including labour etc.
The sound we dread to hear is the cricket sound which is this.
When I had all my belts and pulleys refreshed it cost me $1200 AUD including labour etc.
MBWorld Fanatic!
Joined: Sep 2016
Posts: 1,718
Likes: 608
From: Australia
⏱️ 700HP Facelift converted C63 S Coupe with Drexler 3.06 plated LSD
Junior Member
Joined: Jan 2023
Posts: 17
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From: Texas
2019 GLC63 2021 GLE53 2021 GLB35 2008 E350 2001 SL500
The car has been making me nervous lately. In the past two months I got a low coolant warning which did turn out to be true. I topped off the coolant and everything has been good since. The tank has not lost coolant since and no obvious leaks anywhere so I am unsure where the coolant went. A few weeks ago, I got a low oil warning which was odd considering I had an oil change back in October. I pulled the dipstick and it looked fine and after some research I found that the sensor could go bad. The warning went away at the next restart and hasn't come back since. I don't believe that problems solve themselves so both of those live in the back of my brain almost every time I drive the car.
Now it is making this sound, I can't find an obvious source under the hood but its new. Is it a belt of some sort? I can't even see any belts under the hood so its hard to tell. I'd love to better describe the sound to you all but its a rhythmic sound that runs in time with the motor idling. The car has 57K on the odometer so my fear is that this is the new norm. Runs and drives beautifully as always.
The obvious answer is to take it to a mechanic which I will do but usually I have an idea of what I am in for before I go. This time, I am unsure.
Now it is making this sound, I can't find an obvious source under the hood but its new. Is it a belt of some sort? I can't even see any belts under the hood so its hard to tell. I'd love to better describe the sound to you all but its a rhythmic sound that runs in time with the motor idling. The car has 57K on the odometer so my fear is that this is the new norm. Runs and drives beautifully as always.
The obvious answer is to take it to a mechanic which I will do but usually I have an idea of what I am in for before I go. This time, I am unsure.
http://ultimatepd.com/2015-2021-merc...idler-kit.html
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Joined: May 2021
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Thanks for adding a sound clip. I had a very similar issue on my GLC63, I replaced the belt and right side tensioner and the noise went away. Check all parts to make sure the sound is coming from the left or right/tensioner or pulley. There is an upgrade kit for the pulleys I attacked a link, could be better than the stock plastic one's and keep this issue fixed for longer.
http://ultimatepd.com/2015-2021-merc...idler-kit.html
http://ultimatepd.com/2015-2021-merc...idler-kit.html
I've got the link saved. I am dropping it off today at my mechanic and we will see what happens next. Prevailing hypothesis is that this is the problem. This kit is interesting for sure.
