. It sounds like thin metal vibrates, which is attached either on the engine or exhaust pipe.
Loose rattle noise at cold startup
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2016 C300 w/ sport package
Loose rattle noise at cold startup
Anyone else notice that at cold start there's a rattly noise near the engine, almost sounds like something is loose? Almost like a loose heat shield or something. Having the AC on definitely makes it louder, many times turning off the AC makes the noise go away. Sometimes going in reverse also brings out the noise. It's a very brief noise that goes away as soon as the engine warms up more. It won't last for long. I just took it to the dealer and they basically said it's normal direct injection sound at cold startup but I find it hard to believe having the AC on would make direct injection louder and turning it off would make the noise go away? They also checked to see if my car was affected by the wrist pin issues and determined it wasn't.
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2016 C300W4 (W205), Luxury Pkg, Diamond Silver Met. and Silk Beige\Espresso Interior
Anyone else notice that at cold start there's a rattly noise near the engine, almost sounds like something is loose? Almost like a loose heat shield or something. Having the AC on definitely makes it louder, many times turning off the AC makes the noise go away. Sometimes going in reverse also brings out the noise. It's a very brief noise that goes away as soon as the engine warms up more. It won't last for long. I just took it to the dealer and they basically said it's normal direct injection sound at cold startup but I find it hard to believe having the AC on would make direct injection louder and turning it off would make the noise go away? They also checked to see if my car was affected by the wrist pin issues and determined it wasn't.
For those of us who've complained to the dealer, we've all been told either the central fuel rail or turbo waste gate chatter.
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2015 C300 4Matic Sport
There was the dreaded "wrist pin" issue that plagued some 2015s that required an engine rebuild, but it looks like your car is a 2016.
Most of us hate the normal clunky sound of the 4 cylinders. There is a loud "tick tick ticky" sound after cold startup (injectors??), but it goes away after a few minutes.
There is also a loud "weeeeeeeee" then metal clank clank! that happens when you stop and press the park button. (roll the window down before first)
Dealer says it's all normal.
Having said that, you still may have a valid problem. (since we can't hear your car noise)
Most of us hate the normal clunky sound of the 4 cylinders. There is a loud "tick tick ticky" sound after cold startup (injectors??), but it goes away after a few minutes.
There is also a loud "weeeeeeeee" then metal clank clank! that happens when you stop and press the park button. (roll the window down before first)
Dealer says it's all normal.
Having said that, you still may have a valid problem. (since we can't hear your car noise)
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2016 C300 w/ sport package
Figures when I decide to take the video it decides to be super quiet lol. It's not really a tick or clank noise, more of a rattle. I'll see if I can get a video when it decides to be louder.
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2015 C300 4Matic Sport
Use VLC app Select, media => convert/save => add file => convert/save => profile: audio - mp3 => destination => start.
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2015 C300 4Matic Sport
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2016 C300 w/ sport package
I was in the process of researching other dealers in the area to take my car to to try and fix the noise lol. So it's not a loose heat shield or something and is perfectly normal for these cars?
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2015 C300 4Matic Sport
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2016 C300 w/ sport package
Lol no trolling here, realeric's comment made it sound like it was a noise that wasn't supposed to be there so that made me think even more it was a heat shield. As long as it's a normal weird *** rattly noise they all make I'm good with that.
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2016 C300 w/ sport package
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2018 C43
I revved it that time because that's the only way it brought out the noise. Sometimes it'll make it just idling like with this time.
https://youtu.be/jgaf5JP3oKg
https://youtu.be/jgaf5JP3oKg
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2016 C300 w/ sport package
Idk to me the noise is more rattly sounding than a "tick" and too sporadic to be considered the fuel injectors but I could just be misinterpreting the noise. It's also strange that most of the time it comes when the AC is on, sometimes with it off but for whatever reason the AC brings out the noise. I'll just try and accept the noise as normal and if it starts making it after the engine warms up or gets much louder then I think it's worth looking into more.
