noka

I picked up my E350 4Matic about 2 weeks ago and haven't put many miles on it (only ~550) due to being home for the holidays plus a few vacation days I had to use. Yesterday I took it to a touch-less car wash that I have used with several vehicles already.

Update (12/20): The car wash had nothing to do with the noise. Totally coincidental. The car only had maybe several hundred miles on it and the noise started after I was on the highway and it had already dried out. As I found, it only happened in dry weather conditions. The bulletin described later in this thread which the tech applied, seems to have solved it.

On the ride home I noticed a kind of chirping/squeaking sound. It actually sounds like a squeaky wheel on a supermarket cart. It only happens at highway speeds (I'd say at least 60-65 or so). It does not get any louder with speed beyond that and it's somewhat intermittent. If I open the driver's window, it seems like it's external but the wind noise makes it difficult to determine from where. It doesn't really seem like a sound from the brakes but who knows. Although it happened after the car was washed, I can't really see any connection to that (probably just coincidental).

I ruled out the ventilation system (shut it off), the radio/Comand (shut it off). I also notice it whether accelerating or coasting and if I shift to neutral and coast, sport or comfort mode. Steering doesn't seem to affect it either. So I have some idea of what it is probably not.

I'll bring it in sometime later this week and let the MB Tech ride with me to listen. I have a feeling this type of thing will be difficult to fix if only because you can't really be standing outside to listen to where it's coming from. It's really spoiling an otherwise superb ride and is loud enough that I hear it with the radio on.

Live Oak

There have been some instances here of the hood pads, that contact the body when the hood is closed, making a squeaking sound.

A little lubrication.

??????????? worth checking

noka

Thanks for the idea. It makes some sense because the noise does not change in frequency with speed but requires some minimum speed to occur. My sense is that it's a little too loud for a hood squeak but I'm not really sure. I searched for some similar posts with a description of the noise but haven't located one yet. I looked under the hood last night but nothing was obvious to me. This morning the noise returned maybe 1/3 of the way into my 40 min commute (about 68 mph + or -). I'm taking it in for service for them to inspect in a few days.

hyperion667

good luck noka in tracking it down.....sounds annoying

Mbracer26

I experienced the same chirping sound from the engine bay while on the highway the other day. Sounded like a bird in the engine bay. I remember the AMG model having a noise problem with grill, wonder if its the same issue affecting the e350's.

noka

That's how I could also describe it! It's a little cold wear I live now but when it happens and I open the driver's window, I can sort of hear it outside (i.e. like it's not coming from inside the cabin). Do you notice it happening at any particular speed/range? I sure hope they have a clue when I bring it in.

Trancebolt

interesting... the sportline option on the e350s gives it the amg front fascia and side skirts, possibly resulting in that same sound being on other e classes than the 550/63 amg...

I dont hear that specifically but im going to tune into it now;

noka

In my case, it's difficult to ignore and can be heard with the radio on.

sigx5

since you mentioned this happened above 60+ mph & coming from the hood, check this out, https://mbworld.org/forums/e-class-w...ml#post6149979

maybe the issue is related with this: TSB LI88.20-P-058905

noka

I assume this is the TSB you refer to:
LI88.20-P-058905 Apr14 – e63 wind noises area of bumper/engine hood between 45-80 mph, gap between trim and bumper greater than specified dimension remove front bumper and glue chrome frame to ensure stability.

I'm not sure that it's coming from the hood area. Someone suggested that and it made sense from a physical standpoint but it's difficult for me to locate the noise. I wouldn't really describe it as a high pitched hum. It's not really a constant frequency but more like a squeak/chirping sound (like a noisy supermarket cart with squeaky wheel). I would have thought this TSB wouldn't affect my vehicle, since it was manufactured in Sep-2014 (2015 model year) but maybe not.

Arrie

You have any spoilers in the rear? You say the noise appears at highway speeds and started after a car wash.

I have both roof and trunk lid spoilers and both had failing tape. Had the trunk lid spoiler replaced under warranty but it failed again. I used two-sided tape myself for a fix and it has been good since. MB does not seem to have the best tape on their parts.

The car wash could have knocked a spoiler loose in one end if you have them...?

sigx5

mine car was produced in Apr/ 2014 - dealer fixed it under TSB
my friend's car was produced in Jan/ 2014 - dealer fixed it under TSB

noka

OK, mine was produced several months later, but I'll ask anyway.

noka

I only have the factory trunk lid spoiler. Although it was a touch-less carwash, I suppose anything is possible.
Update: The spoiler seems tight.

Mbracer26

One of my cars is the same production date as yours with the same problem. Do you mind uploading a pic of your paper work so I could show the stealership if they deny the noise? Thanks in advance.

Mbracer26

It was at highway speeds, above 60mph. Thought it was a bad or squeaky ball joint, belt or something. Didn't think of it too much, will focus on it tomorrow.

noka

Today was the first time in a few days that I didn't hear the sound. The difference was that it was raining (lightly) today. This supports my suspicion that it is coming from outside the cabin area and was probably being lubricated by the moisture, thus eliminating the sound. I'll see if it returns tomorrow when I think the forecast is dry.

noka

Update: Brought to the dealer this morning. The tech took a ride with me and definitely heard it. Confirmed it sounds like it's coming from outside and probably "wind" noise somewhere. He's keeping it for the day and maybe through tomorrow as necessary. He said he has some audio sensors he can plant in various places to be able to isolate the source better while driving. I don't expect a quick diagnosis/fix but I can hope.

PeterUbers

I like that they are taking you seriously

wanderfalke

Sound like you have a real bird dog tech. I bet you will get satisfaction.

noka

The tech taped up some areas around the front grill and said the noise disappeared when he test drove it, so he believes he has it isolated. However, he did not remove the grill completely and tried to put some type of insulation in there but it's still occurring, so I'll bring it back next week and get another loaner. He didn't find the technical bulletin further up in this thread (for E63 wind noise) but something similar for E350, also related to front grill. So he will be removing the grill completely and possibly apply some additional insulation or whatever is prescribed. Sure hope he gets it this time.

konigstiger

LI88.20-P-056908 (212 facelift)
https://mbworld.org/forums/e-class-w...ml#post5772146

LI88.20-P-058905 (e63)
https://mbworld.org/forums/e-class-w...ml#post6039468

noka

This one could apply although the date is over a year before my production date of 9/14. It has a link "see picture" but the link is not active. Do you have any further details about the fix?

Tech said he couldn't find it (at least not related to my model '15 E350 4Matic) and probably did not apply.

konigstiger

Not sure why "picture" shows as link, related photo for both is at bottom of each post.

noka

Thanks. I see the pic for LI88.20-P-056908 AUG13 points to the chrome trim but only says that the noise can be caused by a gap. Do you have any details about the specific fix (i.e. procedure and materials used)?