ambitioussteve

PLEASE PLEASE HELP GUYS!! I have an intermittent from little vibration to nasty (like a harley motorcycle) vibration felt through steering wheel, seats, & Chasis of my '07 S550 (88k) [Not 4matic] when stopped at a light in "D". Goes away in "P" or "N" also goes away if I raise RPM's by 50 however it's still present when raising 50 RPM but much smoother of a vibration when doing that. Again it's intermittent as 30% of the time the vibration is almost non existent, 70% of the time it is there annoying the heck out of me In the last 500 miles I've changed: Both Motor mounts, & Trans mount, all Spark Plugs OEM, all air filters, cleaned throttle body by hand, also ran BG44 (cleans fuel injectors), Replaced all 4 Camshaft Magnet Solenoids (Mercedes TSB with updated Magnets, easy DIY). BUT Vibration still there! HOWEVER, when I take the serpentine belt off everything is smooth as butter in "D". All pulleys feel fine and free spinning, alternator has a whining sound, but pulley spins PERFECTLY & Voltage is fine. This is killing my driving experience & depresses me each & everyday! Someone please reach out to me and fully explain in detail what else to do since mechanics tell me (oh it's normal, just the way my car is) No way! I have driven/owned many many Mercedes models between my father & I and this is certainly not normal & I am tired of wasting money changing parts.
F.Y.I. My M273 engine is not effected with the balance shaft timing chain issue, the engine serial # is good. ALSO, if I am in "D" & slightly turn the steering wheel by putting pressure on the steering wheel pump but not actually turning the wheel I feel a vibration manifesting as well. Please & Thank You MB World.

Kevinbeth

I'm new to Mercedes so I can't speak first hand but I have experienced on other vehicles when the clutch in the alternator starts to fail it can cause a similar condition.

ambitioussteve

Thanks...Hmmm...interesting. I would replace the Alternator immediately if I knew for sure it would rectify this. Dealerships want $1,300 for a rebuilt Bosch just for the part I called 3 dealers. Luckily on eBay I can get a brand new OEM for $450 Bosch 220amp.
Anyone else have any other guesses before I replace the Alternator.

kjb55

I started experiencing what you (OP) describe above. By using the UB Voltage reading on the dash - the vibration coincides with voltage readings dropping below 14 volts when coming to a stop. Sometimes as low as 11 volts. I drove same car as mine and that car has a new battery - voltage never drops below 14.2v when coming to a stop, no vibrations. On the occasions my car does not drop below 14v, no vibration. I'll be getting a new battery (decided on OEM AGM 005 541 10 01) and Alternator with clutching pulley to reduce vibration. I'll report back.

(As a side note - I ran diagnostics on both the auxiliary battery, battery switch over relay and battery management module - all passed. The main battery is 12.0 volts after overnight and has reported via Battery Management below threshold that convenience features needed to be reduced. Auxiliary battery reads 12.7 overnight.)

Drives550

Hope you didn't replace the alternator. I have, I think, noticed a similar tendency in my car. Changing all the mounts helped, but that's the only thing that has had any effect. Unrelated but at the same time, the alternator was replaced - made no difference. Also replaced a drive pulley, and drive belt - also made no difference (though the car did get noticeably quieter, which is nice). Changing the starter battery also did nothing to reduce.

I'm stumped, but I don't think the alternator is going to make a difference.

kjb55

Did you or are you able to read voltage in real time to see if the vibrations correlate to drop in voltage?

kjb55

Good news - all the vibrations are gone. Due to timing and parts received - I did all the work at once which is the bad news in that I can't specify what solved the issue. The car is an '06 W211 (211.056) - same symptoms as OP. W221 alternators have clutching pulleys - W211 don't. My replacement - I spec'd a clutching pulley. When I did my balance shaft - I did OEM motor mounts. I also changed the battery - OEM AGM. The voltage drops are gone (see my post #4) along with the associated vibrations. Auto Electric International is the best in the business, btw, http://www.aeimich.com.

Clutching pulleys are known to fail before an alternator fails in terms of charging - essentially causing the symptoms of a slipping belt, but mechanically within the pulley. Hope this helps.

Drives550

kjb55

With code 910 (check your data card www.datamb.com) the clutching pulley is A272 155 05 15.

Drives550

Great information, thank you for following up.

I've already got a new battery, pretty new mounts (all 3). Next chance I get I'll have this swapped out and update here. May be a while - car was just in the shop and life doesn't give me much time to shade-tree these days.

ambitioussteve

To Recap: UPDATE VIBRATION FIXED!!!!!!!!!
2007 W221 Mercedes S550 (88k) Not 4matic
At Stop Lights car chassis vibrates, droning sound, steering wheel vibrates like crazy!!
Car has Brand New Following:
-Both Motor & Tranny Mounts
-Bosch 220amp Alternator (This particular car absolutely does not have a clutch pulley on the alternator) Not the original nor the replacement, I AM POSITIVE. Ebay sells brand new for $440 ship!
-Water Pump
-Spark Plugs
-Air Filters
-I Ran BG44K Injector Cleaner
-Serpentine Belt
-All Pulleys & Tensioner Pulley
-New updated camshaft magnet sensors
(FYI Car engine serial # is not effected with balance shaft, timing gear issues)
SOLUTION:
When in nuetral/park car idles 640 RPM nice & smooth. In gear/drive car idles at 560 RPM and bogs a tiny bit to cause vibration almost like A/C Compressor is putting too much load. Serpentine Belt off car it is smooth in gear! Interesting?
Also Car is perfectly smooth if you use OBDII Bluetooth to watch current RPM's & raise RPM's from 560 to 600 while in gear with your accelerator pedal. Mercedes Dealer said my car couldn't be manually raised the idle RPM no way now how IDIOTS, I called several dealers in my area. Took to Mercedes Indy Shop he raised RPM in gear from 560 to 600 problem 100% solved!!!! Nuetral RPM still stays at 640. He had to go in test mode on SDS to adjust! Weird situation as my torque converter everything else works 100% just needed it's revs raised. THANKS EVERYONE

Finer6527

[QUOTE=ambitioussteve;7372790]To Recap: UPDATE VIBRATION FIXED!!!!!!!!!
2007 W221 Mercedes S550 (88k) Not 4matic
At Stop Lights car chassis vibrates, droning sound, steering wheel vibrates like crazy!!
Car has Brand New Following:
-Both Motor & Tranny Mounts
-Bosch 220amp Alternator (This particular car absolutely does not have a clutch pulley on the alternator) Not the original nor the replacement, I AM POSITIVE. Ebay sells brand new for $440 ship!
-Water Pump
-Spark Plugs
-Air Filters
-I Ran BG44K Injector Cleaner
-Serpentine Belt
-All Pulleys & Tensioner Pulley
-New updated camshaft magnet sensors
(FYI Car engine serial # is not effected with balance shaft, timing gear issues)
SOLUTION:
When in nuetral/park car idles 640 RPM nice & smooth. In gear/drive car idles at 560 RPM and bogs a tiny bit to cause vibration almost like A/C Compressor is putting too much load. Serpentine Belt off car it is smooth in gear! Interesting?
Also Car is perfectly smooth if you use OBDII Bluetooth to watch current RPM's & raise RPM's from 560 to 600 while in gear with your accelerator pedal. Mercedes Dealer said my car couldn't be manually raised the idle RPM no way now how IDIOTS, I called several dealers in my area. Took to Mercedes Indy Shop he raised RPM in gear from 560 to 600 problem 100% solved!!!! Nuetral RPM still stays at 640. He had to go in test mode on SDS to adjust! Weird situation as my torque converter everything else works 100% just needed it's revs raised. THANKS EVERYONE [/QUOTE
Thanks for sharing your situation!!! I have a similar problem on my 07 s550 4matic 60k, and have been following your quest to find a solution. There are a lot of posts were people do not come back and report the repair or what fixed the problem. So thanks again this helps a lot….

I have the same noise at idle, with the car in drive, stopped at a light. If I put it in neutral, or with the car in park it does not make the noise. I thought it might be related to the engine load when in drive that may be bringing down the RPMs, but was not sure. I was thinking it might also be carbon build up on the valves or pistons bringing down the idle? I have had the car for just under a year and there was no noise for the first 6 months. I do know my motor mounts are shot and needing to be replaced. They are contributing to the noise. Now I will be looking for a shop to raise the rpms. Anyone know a good independent shop in North East IL?