metallic rattle at low speeds..
 

Lately I've been noticing that at low speed, light acceleration, I can hear this metallic rattle coming from the front of the car...it's not so much of a rattle, but a metallic "zing", haha. I really don't know how to explain it. It's not pinging, but if I turn my A/C and radio off, I can hear it from the inside with all windows closed. It also seems like my engine is producing a slight crunchy vibration through the gas pedal thats become more apparent when accelerating, or even coasting. Any suggestions? :nix: Also, sorry for my poor choice of adjectives and verbs, they were the best that I could come up with.

That is a tough one to diagnose without being in the car. It doesn't sound good as you can hear it and feel it. I would take it to the shop ASAP.

I believe I may have recently started experiencing some of the same issues on my 350. It's a slight noise at low speeds and usually when I'm turning left or just have turned left.

Have you had yours checked out yet?

I had the same, you know what I found out?! It was my MB keychain that was ratteling. I grabbed it with my right hand and the sound was gone!

Can this be what you where hearing? :zoom:

While I was waiting to pick up my car on Friday, I was talking to a woman who had her C300 4Matic in for the same thing. They had to replace something in both front struts to cure the "ping" noise. But her description was almost the same as yours.

Mines a low RPM metallic rattle that comes from what sounds like underneath the front of the car. It's not pinging, but I can hear the sound reflect off garages etc. You'd have to hear it to know I guess.

A bad fuel injector??

I read your post and thought I might be about to experience a "duh" moment, but that wasn't it.

It isn't a rattle so much as a whine-type noise...similar to the noise you hear when say a drive belt starts to go bad.

Whatever it is it is coming from the front left of my car. Front struts could be the problem. I've got a few other issues to get checked out so I'll add it to the list and report back what becomes of it.

Sorry to revive a 5 year old thread. But I was wondering if you ever figured out what the issue was? I have the same problem.

Me as well! I am scared its going to be extremely expensive.

Same issue!
 

Have been hearing this metallic ping or rattle when at low speeds it echoes and is clearly heard had the mb dealer re grease the front axle where they meet the hubs, etc new bearings but still there? I know it’s an old thread but any one solve it?

Me too!! What is this sound. I have a 2017 C43. Bout 60k miles. I took it in twice first time they said it’s coming from exhaust it’s a flexing in the system and since I got a new exhaust system the sound should of went away but the sound is still present.
second time I had the lead tech do a ride along and he stated it was from the turbo bleeding off air. But it was in a slow acceleration so I’m not sure. And it was a “ normal sound” meaning nothing to fix. But wasn’t present when I got the car. Any suggestions

I think I may have recently found that low octane fuel will cause a slight tapping at low rpms. I'll keep you posted.