Newbie air matic question
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Junior Member
Joined: Sep 2021
Posts: 17
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'11 E350
Newbie air matic question
To start, my car is a 2011 wagon with 57k miles on the clock. I've been noticing that when I shut it off, the suspension lowers very slightly (this is barely noticeable). It does sit for a few days on occasion, but it never goes down any further. Also, when I start the car, I hear the rear air compressor kick in momentarily as I start driving . On rare occasion, it kicks in randomly while driving for longer distances and is somewhat loud. Is this normal or should I explore this further?
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Joined: May 2021
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From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Your vehicle definitely has a leak, and if it is not addressed your compressor will wear out earlier and more $$ since you will still have to fix the leak
Start by scanning the car for codes, and we can go from there
Start by scanning the car for codes, and we can go from there
Super Member
Joined: Feb 2019
Posts: 681
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From: FL
2012 E550 sedan 2019 E63 Wagon
To start, my car is a 2011 wagon with 57k miles on the clock. I've been noticing that when I shut it off, the suspension lowers very slightly (this is barely noticeable). It does sit for a few days on occasion, but it never goes down any further. Also, when I start the car, I hear the rear air compressor kick in momentarily as I start driving . On rare occasion, it kicks in randomly while driving for longer distances and is somewhat loud. Is this normal or should I explore this further?
The first 2 parts are normal. The loud part during long distance driving is not normal.
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Joined: Oct 2010
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
To start, my car is a 2011 wagon with 57k miles on the clock. I've been noticing that when I shut it off, the suspension lowers very slightly (this is barely noticeable). It does sit for a few days on occasion, but it never goes down any further. Also, when I start the car, I hear the rear air compressor kick in momentarily as I start driving . On rare occasion, it kicks in randomly while driving for longer distances and is somewhat loud. Is this normal or should I explore this further?
Car slightly lowers down when you park it because the system pumps air in the springs against the down force that is generated with the moving car. When the car stops this down force goes away. If you keep the car running on idle long enough after stop it will lower down before you stop the engine but normally you stop and leave the car too early for this to happen so when you leave the car and lock it the car knows driving is done and lowers itself to the set level. This is the slight lowering you observe.
Thread Starter
Junior Member
Joined: Sep 2021
Posts: 17
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'11 E350
Thanks for the feedback! One thing I should mention is that the car has a rebuilt title due to being hit in the rear. When I bought the car, I couldn't hear the compressor, but it was also missing the cover. I installed a second hand cover to protect the compressor from the elements and that's when I started hearing the sound. Maybe it's missing some king of a baffle?
MBWorld Fanatic!
Joined: Oct 2010
Posts: 5,141
Likes: 1,293
From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
Thanks for the feedback! One thing I should mention is that the car has a rebuilt title due to being hit in the rear. When I bought the car, I couldn't hear the compressor, but it was also missing the cover. I installed a second hand cover to protect the compressor from the elements and that's when I started hearing the sound. Maybe it's missing some king of a baffle?
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Joined: Jun 2020
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'11 E350, '11 E550, '98 M3, '95 E320
The intake to the compressor is routed up behind the rear fender well... a rubber hose with a filter near the compressor. The compressor itself is suspended via springs from the chassis. All of which is enclosed by a plastic guard.
From the outside I can hear the compressor run... inside, it would have to be stationary. Under way with radio, I cannot hear it.
From the outside I can hear the compressor run... inside, it would have to be stationary. Under way with radio, I cannot hear it.
