MbBiturboFan

Hi all, I have a 2009 W211 E63 AMG with 147k miles, still on the original airmatic struts.

While vacuuming the car over the weekend, I heard a sudden high-pitched hissing noise, as if air was leaking, from the driver's side wheel arch which lasted about 15 seconds. When I turned the car on, I can hear the compressor running and the car rising. It tries to stay up and actually stays up while the compressor is running (constantly trying to keep up), but upon turning the car off, the car sags again, although only on the front driver's side.

I already ordered new Arnott Remanufactured units (AS2300, AS2301) but realised that the airmatic lines connect to a valve body which in turn is connected to the compressor. As the car sags only in one corner, could there be another issue, besides the airmatic struts (which are expensive), that can be fixed relatively easily/cheaply? Upon reading other members' issues, there could be an issue with the airmatic line, like a simple plastic line replacement or simple re-tightening of the connection bolts. I don't think its a compressor issue.

bbirdwell

It's the strut.

Yuille36

Yes, I agree with bbirdwell assessment, replace your front struts in pairs, as you've got 147K on them. It was just a matter of time before they would fail.
I got 93K out of my original air struts, before one of the fronts kicked the bucket. I also replaced my air compressor, and valve distribution block as well, out of abundance of caution.
As valve blocks tend to leak as they age.

SleepersRock

Same here. I had about 95k on the fronts when they went. Then the rears went out at 100k. Exact same issue as the OP had, except mine is lowered via link and I have carbon fiber side skirts and a front lip which made towing the car to the shop a *****. I suggest getting it fixed before that happens to you.

Yuille36

When my front air strut failed, of course you get the red "Stop Car too Low" warning. I however drove slowly to my shop about 2.14 miles away, I knew that most likely my air compressor would burn it, as it was all original to the vehicle.
But, since I was replacing it as well, I didn't care. Well, I made it to my shop, and they had a nurse it onto the lift, using a floor jack. As the entire system was devoid of air. But, I knew that calling a flat bed truck wouldn't solve my problem but create another headache trying to get it on the truck.
But now, I have a completely new airmatic system, front struts and rear bags, new air compressor and valve block.

CharlyE500

Or you can do coilover conversion.

E63007

I don't meant to hijack this thread, but being that its one of the latest threads about a subject there are hundreds of threads about, I thought I'd posite my query here regarding my Airmatic Issue!! For Starters, I have since the dawn of the CCP Virus installed newly rebuilt (by RMT) Front AirSprings and Rear Air Bags along with new OEM Rear Shocks and a new Arnott (FCPEuro) Air Compressor. The complete list of items I've installed goes beyond the scope of this discussion. I can manually set my ride height in Xentry>DAS with no issues until the morning when it drops to a Seemingly "PreSet" Level? This PreSet Level seems to fall right where it probably can safely sit, that being around 26" from Ground to Rear Arch & 26.5" in the Front Arch (ie-3.1 degree front & -1.5 degree Rear). I'll most often immediately ReSet it in DAS whereby it will show the levels being approximately 6-11mm too low, too low that is compared to my "Manually Adjusted Settings" where I have chosen to have the ride height on the taller side (4.1 degree front & -0.9 degree rear). In reality I intentionally mislabel to say 3.9 & -1-1 just so that if it goes higher for whate4ver reason, the voltages will be safe. As to the voltages themselves when being set Manually, they are all well within the range with room to spare. I have spend several sessions at the Alignment Shop trying to dial my Alignment (I also have completely rebuilt my Suspension For and Aft and added UPD Rear Toe Arms and F1 Upper Front Camber Arms and New Michelins!) by bringing the Laptop with DAS making certain the Ride Level was set before taking measurements. Unfortunately, even though the alignment has been in spec, the car pulled to the right. Thanks to this shop being very lenient with my coming back again and again (My 4th Shop!) and the Tech willing to go outside the box to "Correct" the pull by adjusting the Toe in the Rear, we got it almost perfect.

But this is where it gets interesting!! I found that when I brought my Laptop>Das and had it connected while I was driving on either side of the Crown in the highway, the Front Level Readings would take a while to switch from say being on the Right Side of the Crown and the right AirSpring side changing from only slightly below -11 (if over 65 it goes minus 10mm) and the Driver Side Left showing -21, to a greater number below (ie -25mm) before it would take time to correct. In effect, it appeared that the AirSprings would adjust so as to level the car and I found this to be cool, but it seemed to take way too long? It wasn't until I pulled over to the offramp and situated myself that I noticed that although DAS was showing me the Level Height(s), I couldn't press F3 to get the DAS to reset? So I turned off the car, unplugged and replugged the DAS OBD connection and restarted my computer to reload DAS (which take a minute or so) and then noticed when trying to Reset The Ride Height that I got the message that the Compressor needed "3 minutes to cool down"!!! So it was here where I deduced that it may be the Valve Block Releasing Air when I was going over and over the Hump/Crown. And because the Valve Block is pretty much the only thing DAS can't really Diagnose, I further surmised that by switching side of the Crown may have caused the Compressor to run excessively since if the Valves for the Front are leaking, then even if the Reservoir had released Air to correct, if there's a leak at the Valve Block it would "Switch" perhaps to the compressor? Who knows, maybe even the line from the Reservoir to the Valve Block leaks a little too?? Which would further cause the Compressor to run overtime??

Needless to say, when I would straddle the Crown to see if my car was Aligned correctly, it would seem to continue to pull to the right, that is until the AirSprings would ultimately adjust to the right settings, albeit slowly and then it would not "Pull". When going for a test ride after the last alignment, I had not come to this deduction nor did I have the laptop opened with DAS as it was out of battery power!! And, as you would have it, when I was in the passenger seat with the Tech Driving, there of course was no pull!! It wasn't until he accelerated that he could experience "Torque Steer" as he called it. On my Lifted Jeep, Torque Steer occurs in the Front, but that is completely a different animal!!

10/15/21- So I once again connected to DAS and set the Ride Height, but this time I filled up the Reservoir to about 14 Bar and then went back to the menu where you can select each AirStrut's Pressure Levels along with the option to select Airmatic Pressure Valve B7. Interestingly, B7 would show a slightly Higher Pressure than each of the others. So if B7 showed 14 bars, the others would show perhaps at Max a bar less than that. But as I swapped back and forth thru each menu I noticed that after a few minutes the Pressure would lightly decrease and continue to decrease, for all the Struts and for the B7 itself!!! Being that I can Lock the Rear Struts and increase Air if say I'm raising the Front, coupled with the fact I've done similar when lowering the front onto Ramps followed by lowering the rear, I know the Valve at the Strut can lock and hold air. I should hope so since they're all new!! So that leaves the Valve Block as being the most logical culprit!! If it were to leak at all times, especially upon increasing it with pressure, then I would say it would be a Line Leak perhaps somewhere between the reservoir and the Compressor or anywhere else for that matter. But the fact that it holds pressure with more pressure (14bar) and then gradually looses it from there says to me that its most likely the Valve Block. I sure hope so anyways!!