rmt52

Hi guys,

I have a question for you. Would anyone be able to explain to me what the whine/whooshing noise is when the acceleration is pressed at low speeds/gears on the c63 (lets say less than 40 mph), it's distinct from the awesome growl/rumble the engine emits when pressing on the gas. I tried to record it but it was hard to do without getting a lot of wind noise, will try again later. I did find this video and you can hear it at 0:25 onwards in the video and to a lesser extent when the guy starts his car at 0:09. Just curious because in past cars i dont recall hearing that type of noise when accelerating, then again i didn't use to get to hear the amazing rumble of the v8 engine either.

http://www.youtube.com/watch?v=Ht5Ko...ature=youtu.be

rmt52

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roadtalontsi

Unless you someone installed active body control hydraulic suspension on your c-class (would be a first ever) you dont have a pulsation dampener.

rmt52

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m a x i m u s

isn't that just pulley noise? I have the same sound in mine, at least the same as appears in the video. I also find that sound annoying.

Mode Carbon

iTrader: (-1)

+1

Have had a similar noise

rmt52

I took it to the dealer, they said the pulleys were fine. I spoke with a SA at a dealer he spoke with the shop Foreman and described exactly what I've been still seeing, they're going to check everything again next week. I hope it gets sorted out.

roadtalontsi

your right it does exist... the 273 and 156 motors have them when used in an sl , cl, or s-class when equipped with abc. Notice at the top how it says vehicles... 216 (which is a cl- all cl's have abc as do 230 sl's)
" Models:
CL 500 4MATIC BlueEFFICIENCY 11-12, CL 600 07-12, CL 63 AMG 08-10, CL 63 AMG 11-12, CL 65 AMG 08-12
==========
Chassis:
216374/65V, 216376/65V, 216377/65V, 216379/65V, 216394/65V
========== "

Your car does not have this part. . I always considered this noise to be normal oil pump noise, the slk55/c55's also make the distinct groaning noise similar to a power steering pump low on fluid. the other 55k cars do but the superchargers are noisier than the oil pump. dont worry about it an enjoy the car rather than pick it apart

rmt52

roadtalontsi, are you referring to the groan on startup that goes away as the engine warms up/sits in idle, or the whine that you hear accompanied with the revving like in the video? you're right about the part, it's for the m156 engine but not for the c63. i see that now, my mistake. the guy that had posted this for his e63, said that he had an issue with the pulsation damper and had described the noise exactly as i would and in the exact circumstances as well. He said it's like the whine noise old cars make when they reverse, mind you a bit less pronounced. If you guys are saying you all have this noise too when youre driving in 1-3rd gear at low speeds, where the actual growl of the v8 is too quiet to drown it out, then maybe i'm just being paranoid. I dont hear it in 4-7th gear at higher speeds. Was just worried that this was a sign of something failing and was hoping to prevent any damage by being proactive. Anyways i appreciate everyone's comments, it's mildly reassuring that this isn't just something with my car.

rmt52

roadtalontsi, Mode Carbon, m a x i m u s, you guys are probably right.

seems this guy has the exact same noise at 4:08-4:12, 4:59-5:15, and 5:25-5:35.

I guess it really is just normal for these cars. Gotta get used to it i suppose. Thanks for all your help figuring this out. I really appreciate it.

rmt52

in case anyone cares to know, it's apparently definitely caused by a noisy camshaft gear which is a result of the fact that these gears are straight cut? it's also been the source of an infrequent 2-3 second rattle noise that occurs only occasionally when really pushing the car in 3rd or 4th gear (going above 4500 rpm). a mercedes tech told me that he's seen and fixed quite a few of these where the camshaft gears can rattle a little under heavy load because there is a internal gear with a spring and the tolerance can be slightly too much and the reason it might only be doing it 3rd and 4th gears for me, is that the engine computer decides how much to actuate the cam adjuster and it could have different actuation values for the higher gears because it's all speed and load dependent. anyways, just thought i'd follow up with you guys and let you know what i have been told.