rotesau

So just before the 2020 COVID pandemic quarantines started in the US, I managed to get my hands on a 2012 W212 Wagon in, I shall say, remarkable shape for its 97000 miles. The first Mercedes in my family since my grandfather's 190 Ponton from the 60s, so imagine - large shoes to fill, and boy do the shoes feel like walking on a cloud.

So far, the only thing I'd like to chase down and correct is a weird and annoying "rattle-like" noise that can be heard SOMETIMES and comes from the back of the car, I want to say from the rear hatch but not sure - it definitely comes from somewhere behind the rear seats. I have looked in all the removable pieces, the storage access hatches, the folding seats, in the spare wheel compartment, I have tried driving the car with and without the rollup cargo cover / dog net, all to no avail - the noise keeps happening SOMETIMES.

By SOMETIMES I mean sometimes, not always. It's not predictable, but when it happens, it ALWAYS happens at low/moderate city speeds (25-40mph) and when I hit something that creates in high-frequency vibration (say, hitting a bridge's expansion joint, or driving on a cobblestone street). It doesn't really happen at highway speeds.

I'm stumped. Has anyone had to live with a similar "rattle"? Any pointers are appreciated.......

"The noise" sounds roughly like this: Press a metal ruler firmly against a kitchen countertop, leave 5-6 inches of ruler flying past the edge of the countertop, and hit the tip of the ruler with your thumb. That's roughly what it sounds like, only amplified by the car's greenhouse and with no definitive identifiable source, just "back there".

Has anyone had a similar issue?

Arrie

I had a rattle in my 2010 E550 and 2011 E350 and unbelievably also in the 2013 S550 that comes from the fuel filler door lock.

If you go to your fuel door and tap on the panel around it you should hear the rattle.

I had it fixed on both E-class cars under warranty but have not worked on it in the S yet.

This rattle is like you say, it happens sometimes and then it does not under similar driving conditions.

Dane500

Check the screws in your rear tag, especially if you have a surround applique. My 500 wagon does this but I have no provision to screw the lower half of the plate down.

Arrie

That is a good point. I had this problem with my S550 and the fix was to add the two screws on the bottom edge of the plate.

rotesau

Thanks for your replies so far guys.
- I suspected the license plate mount a few months ago, and fastened it tight with 4 M6 screws. "The noise" was still there.
- Today I checked the fuel door, tapped on it, wiggled it, nothing. The rubbery plastic surface surrounding the fuel cap and the fuel tank opening? Nothing, all dull and quiet. Perhaps I'm not looking in the right place?

HOWEVER

- I found my next suspect: The long, thin plastic piece mounted on top of the rear gate (takes the full width of the gate) that hosts the 3rd brake light. I noticed that this piece has a gap (about 1/16" or less, perhaps) between it and the sheetmetal of the gate, and I could see potential for this piece to vibrate and hit the metal. I'm thinking of putting little paper or cardboard shims in the gaps and go for a test drive to check it out.

Will report later....

Arrie

Around the fuel door. I may have not been clear in my previous post. With the side of your fist “hammer” the quarter panel behind the door. Rattle is not from the door, it is from inside the panel if you have it. I was told by mb it is the plunger that locks the fuel door.

Toadroller

Another thought. I lowered my back seat today and then lifting it back up to slam it into place it made a vibrating sound like you described. Are your back seats solidly in place? Simple check.

p30amg08

Yes, its the "60" portion of the 60/40 split rear seat. Fold down the 60% and drive, see if it still makes the sound.

rotesau

@Arrie - Tried and tapped everywhere and wasn't able to find anything even remotely loose or wobbly. But point taken, thanks... will keep it in the backburner if I ever hear something coming from there.

@Toadroller @p30amg08 - So, Friday I had to carry something large - best opportunity to test out your theory. I started by lowering just the "wide" portion of the backseat, on my way to pick up the stuff. Drove up half Brooklyn and half Manhattan, deliberately took some cobblestone streets on the way. I had to lower the "narrow" portion as well, to fit the stuff. Both driving in and driving back, guess what. NO RATTLE AT ALL. It was almost unbelievable. So unbelievable that I still don't believe it - will definitely keep my ears open on the issue... Thanks a lot!

p30amg08

i left mine down for a few days, put up the seats firmly so they latched correctly and it went away. Knock on phone glass

Toadroller

Huzzah! Hope it works out for you! It's nice when there's a simple fix.

Going off on a tangent... I bought my 11 E350 wagon in March and discovered a cracked wheel, leaking through the inboard side of the rim. $400 later... new (refurbished) wheel, off to the tire place, done. But then a slow leak through the shank of the valve stem (not the valve itself). Off to the tire place again, new valve stem. Month later, rotated that wheel to the front and again, slow leak through the shank of the valve stem. . Took it back yesterday and today, so far, fingers-crossed, no leaks.

It's nice when nice things work.

rotesau

So funny (well, actually not) that you mention it. When I first bought the wagon, I drove it away on a new set of all-season tires I ordered (Nokians). One of them loses air at a - v e r y s l o w r a t e -. I have resorted to pumping it every few months (takes, say, 2 months to lose 6psi). It puzzles me, and I'm hesitant to call this a tire issue, probably more of a wheel issue. And if that's the case, I wouldn't mind just replacing the wheels because mine are the boring 8-spoke design...

SKullman

I'm going to add to this as I too had an odd noise at slow speeds. First off the details, 2013 E350 Wagon Sport Package.

Rear seat, center armrest.

I had the benefit of having my kids crawl around as I drove around our cul-de-sac driving over the man-hole cover. We found it to be inside the back of center armrest, If you lower it and just smack the back with your fist, it will make the noise.
I've tried to include a video, you can hear the metallic noise after the smack. I've yet to figure out how to open the seat up to silence it. Any help would be appreciated.

GreenBeef

Did you ever solve this? I have the EXACT same rattle in E220 estate. Started 6 weeks ago and is driving me crazy. Would love advice on how to fix this. Thanks.

SKullman

I did not. It still does that metal rattle over certain bumps below 40mph.

I haven't spent the time to try and take apart the 60 side of the seat.

GreenBeef

thanks for the reply. I'll let you know if i get any further with it.
Cheers

GreenBeef

HI,

Having spent a lot of time researching i think i have found the culprit from a vid of same issue in C Class Saloon.
My next issue is how to dismantle the 60 rear seat back and access the seatbellt reel. I will just remove that ball-bearing completely.



Hope this helps,
Cheers

Krister

I have this same exact issue on my car:


Have you managed to fix it and how do you take a off the rear seat panel?

CaliBenzDriver

As the post you referenced by @SKullman it is caused by the plastic passthrough. The latch opens from within the trunk not from the back seat.

Jam a napking, a chewing gum or your local taxbill receipt ✌️

SKullman

Except mine is a wagon. But I'll check...

Krister

My car doesnt have a passthrough opening even though it's a wagon.

wongnips

@rotesau @SKullman @GreenBeef

Hi guys,

I just joined this to share my fix of a rattle noise of my mates 2015 e220 estate. The rattle came from the back seat (60 section). Like someone said in a previous post it sounded like a metal ruler hitting or vibrating off a metal surface.

If you punch the backrest on the lower part it will rattle.

So after lots of investigation I found a fix.
It's the backrest part of the seat (the upper part that goes against your back and not the part you sit on, to avoid confusion).
There's a metal bar inside the seat that is very close to the metal back panel of the seat.

To get at this here's what to do:

Unhook the felt cover on the back of the seat. You only need to do the bottom half of it just enough to allow access to the next step.

This will reveal a black metal panel seatback which the upholstery is actually clipped to. So you should be able to unclip the upholstery at the bottom end of the seat . You only need to do enough so you can get your hand in behind the black metal panel.

Now you should be able to squeeze your hand in behind the black metal panel and feel around for a metal bar. It's actually a bar that curves around and comes back on itself. If you pull this you'll be able to make the offending noise.

If you feel around and follow the bar, it curves around and you'll actually feel where the bar comes into contact with a raised section of the metal back panel. This is where the noise is coming from!

Get something to wedge in between this gap. I cut up a microfibre rag and wedged it in. Then tried pulling on the bar again and no noise!

Put everything back together, go on a drive and voila! No noise!

I hope this helps you all. As I said it's not my car and I'm not trained in any way. We had googled for answers endlessly with no joy so I feel this may help. Any questions feel free to message me.

Axredds

Absolutely brilliant! It had bothered me for over a year and it's finally over. I have actually created the account here just to thank you


wongnips

@Axredds Thanks! Great to hear this has helped someone! Happy noise free driving!
It was such a stupid design flaw by Mercedes.

HaLLiS

Hi there, thanks for the info. Just curious as to how you managed to "unhook" the felt from the seat? Just had a look and on mine its solid as.