2007 R350 Hydraulic pump inflation noise in engine bay
Thread Starter
Newbie
Joined: Oct 2009
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2007 R350
2007 R350 Hydraulic pump inflation noise in engine bay
Hello all,
Does anyone know what part in the front engine compartment may be making a hydraulic pump inflation noise? This happens when I start the car after it been sitting for a few hours or so. I also hear a deflating noise in the front engine compartment a few minutes after the car is shut off. Any ideas?
Thanks,
Will
Does anyone know what part in the front engine compartment may be making a hydraulic pump inflation noise? This happens when I start the car after it been sitting for a few hours or so. I also hear a deflating noise in the front engine compartment a few minutes after the car is shut off. Any ideas?
Thanks,
Will
Super Member
Joined: Jun 2005
Posts: 857
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From: NC
2019 Volvo XC90 Magic/Amber, '95 E320 Cabriolet Midnight,'14 GL350 Lunar/Almond was '07 GL320CDI
Hello all,
Does anyone know what part in the front engine compartment may be making a hydraulic pump inflation noise? This happens when I start the car after it been sitting for a few hours or so. I also hear a deflating noise in the front engine compartment a few minutes after the car is shut off. Any ideas?
Thanks,
Will
Does anyone know what part in the front engine compartment may be making a hydraulic pump inflation noise? This happens when I start the car after it been sitting for a few hours or so. I also hear a deflating noise in the front engine compartment a few minutes after the car is shut off. Any ideas?
Thanks,
Will
Junior Member
Joined: Sep 2008
Posts: 35
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R500
Yeah, I think it's the airmatic - I hear the same thing. I think there's a service bulletin on this issue.
T-B-32.22/65 Discharge Noise from Airmatic Compressor
So there might be a fix for it. Have it checked out and let me know.
T-B-32.22/65 Discharge Noise from Airmatic Compressor
So there might be a fix for it. Have it checked out and let me know.
MBWorld Fanatic!
Joined: Sep 2005
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From: Albuquerque
'10 CL550, '12 GL550
According to the text of that DTB, the "fix" was implemented in production as follows:
It's normal for the noise to occur, the DTB is just something to make it quieter.
Dampening mats have been implemented into series production as of January 8, 2007, and modified intake hoses have been implemented into series production as of July 1, 2007.
Last edited by lkchris; Oct 15, 2009 at 06:42 PM.
MBWorld Fanatic!
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From: United States
2008 R350 & 2008 C300
I had the same question, so during a service visit I questioned my service adviser who told me that from 2008+ all R class's have a version of the airmatic system and the noise that comes from the front end is the air compressor. The airmatic system isnt as complex as the old airmatic package, where you could raise and lower the ride height yourself, rather it does it automatically at certain speeds (highway driving lowers, in town raises). I've yet to find anything backing up this statement from MB other than the window sticker that claims "air leveling rear suspension".
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R500 -06 & Corvette -98 Indy PC
Junior Member
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From: Chandler, AZ
06 R500 / 03 CLK430 Conv
I had the same question, so during a service visit I questioned my service adviser who told me that from 2008+ all R class's have a version of the airmatic system and the noise that comes from the front end is the air compressor. The airmatic system isnt as complex as the old airmatic package, where you could raise and lower the ride height yourself, rather it does it automatically at certain speeds (highway driving lowers, in town raises). I've yet to find anything backing up this statement from MB other than the window sticker that claims "air leveling rear suspension".
