Just bought a 2008 W221 with 59,000 on the clock last month. Paperwork from seller stated that they replaced the passenger front air strut and valve block due to not holding air. A few days after I purchased the vehicle I noticed the right front passenger side looked lower than normal so I took it to a local highly regarded MB specialist who agreed with me and performed a ride height recalibration along with a cabin filter, transimission/brake fluid exchange and new spark plugs. All money in $1,274.26. Problem is, the right passenger side still sits about a fingers width lower compared to the drivers side front, but I'm not getting any warning lights on the dash. When I park the vehicle it lowers and hisses. Any input on what to do next ? Is this normal ? I might be answering my own question here but, I only work about 5 minutes away from this shop. Should I just take it back in and have them check it out ?

A certain amount of suspension drop due to thermal contraction is normal, between .75 to 1 inch is within design parameters, and should not be regarded as a malfunction. For peace of mind you can have them revisit to check for leaks leaks.

there's another post below showing a recall (that wasn't a recall !!!!) for a damaged pipe the length of the car on the right rear than causes it to drop exactly as you say

oddly my car does exactly the same but on the wrong side, whilst my car gets the steering wheel on the correct side I don't see the pipes would get swapped

Topic number LI32.22-P-048772 https://mbworld.org/forums/s-class-w...ml#post6627003

This only applies to rear. Xentry bulletin only applicable under warranty. However, if within VIN range, one can argue for MB goodwill repair citing defective pressure line installed @ production.

Ah, OK, I miss read first post, and thought meant rear.

The other thing to do before trying to level, is to check all the linkages to the level sensors are moving freely. Mines only done 60k Miles and I lucbricate the level adjusters twice a year, yet the rear snapped off in the summer !!! and one front was seized.

They are prone to seizure and then snapping, so as only $20 each fit 3 new ones then try and level it up

did you ever find the solution. Because that's exactly the problem I'm having. After I park 50% of the time I hear hissing coming from the compressor like it's venting in the front drops.

How much is it dropping? If it only drops a "set" amount shortly after you park, but doesn't continue to drop if you leave the car parked overnight... then I suspect a non-issue.

I seem to have the problem that I see mentioned here a lot where when I get out of the car I can hear a large vent or a "swoosh" from the presser / valve area. It seems to be venting and I can see the front of the car drop an inch or more. I don't accept the fact that this is normal. Why have something drop that causes the compressor to start up and run to bring the car back up to height every time I restart the car. That is just excessive wear. The car should not be dropping every time I get out of it

Airmatic tries to keep the car “level” at a prescribed ride height. When you unlock and open the door, while driving, soon after you park and exit vehicle... it’s normal so long as it doesn’t keep dropping.

Doesn’t always have to drop, can raise too.

The steeper the incline or uneven surface parked on, would exaggerate the behavior...

had mine 6 years airmatic suspension NEVER makes any noise like that

and ride height never changes with the key out

there are other things the AC does something sometime shortly after parking might be water dropping on the exhaust

This airmatic control algorithm is kind of stupid because the car controls its level (if too high) even when parked.

I now have two cars with it and both do the same thing, they drop after I park and close the door.

This is result of the down force that is generated when car moves. When you stop moving the car raises up as the down force goes away.

In traffic when stopped at traffic the car does not lower as the engine is running and I guess gear selector is on Drive so the car knows it will soon be moving again but as soon as I stop the engine, exit the car and close the door the car lowers to the set level. Both of my cars do this and I believe it is the stupid behavior Mercedes programmed them to do. My opinion is the Airmatic system should not do anything at all when car is turned off.

I have never seen my cars raise after i stop and exit them as I don’t think the compressor runs when car is turned off. If it did you would not see result of leaking air springs other than when it runs battery dead, which the don’t do.

I had leaks on my E-class and when this happened the car dropped over night and then raised right back up when started engine but it never ran the compressor with engine not running or ignition power on.

And it is so funny that the 1985 Lincoln Mark VII LSC that I used to have had this same exact behavior. It lowered the same way when parked and closed the door.

Arrie, mine does not go up or down in traffic, or when parked, or when stopped.... you may have two cars doing it, but unless USA does thing differently something strange is happening on both your cars. First step is to ensue all three the level sensor link rods are moving nicely, otherwise the car will be confused and may do silly things.

I even had my airmatic unit software updated from 2006 to 2008 nothing changes. I've had a new pump and all there sensors changed and to say the back was seized in a huge understatement, even with pliers it is physically impossible to get the plastic joint to move on its mild steel ball.

I agree if you stop on unlevel surfaces (one side of the road lower, or with a wheel on a kerb, when its running), to some extent the car attempts to stay level and this is just mental and pointless. But its subtle and inaudible

All my sensors work fine in both cars. I have checked many times with my scanner. And on both cars level changes also work as designed.

Yup, its pretty complex... I remember reading documentation that stipulated when the car was "waken" and a ride height adjustment was necessary the airmatic looks to see if sufficient pressure exists in the reservoir to make the adjustment. If there isn't, then it waits still the car is started as the compressor draws a lot of amperage. The compressor only runs to refill the reservoir.

I've never monitored while driving with Xentry... but its supposed to check and adjust if necessary the suspension at a certain interval. In addition when you exceed a certain speed, the suspension lowers X mm and then raises when your speed drops. Looking at my compressor time on my 550 in 100k miles, its been running over a million seconds... or for every 10 miles it runs 2 minutes. Granted, when I got it both rear bags were blown... but I suspect in perspective of the age/mileage thats minimal and the system makes a lot of adjustments. Our wagon with similar milage has less compressor time, makes sense it only adjusting 1 axle.

A little correction to my post above. I mention that the car lowers after I park and close the door. I think it actually lowers after I lock the door. Me saying close the door really means the same thing as I always lock the door when I close it even at home as I don’t have a garage.

Hi, where can I get more visual reference / information on your very interesting input, tagged here.
My W221 was parked for long due to my own negligence in dealing with some issues. However before that from time to time, the system sometimes displayed an error when I wanted to raise the suspension. It would show "vehicle rising" but after some time, even though it did rise, a message displayed "malfunction".
The vehicle when parked for the extended periods (weeks/months), sank from all four wheels. Rose when started.
So last month I finally got to it and started the vehicle with the intention to resolve all issues. Drove it approx 120 miles, getting same errors as stated above for suspension "malfunction". After 2 weeks of the limited driving, I parked it and the same night the vehicle alarm rang (beeping sound) middle of the night, noticed that the front right side was lowered to lowest position. Started vehicle, it rose and sank again and did not rise again on its own. There was a hissing sound.
Please guide me to next steps to navigate and identify the exact issue.

Hi, noticed your above post, my vehicle VIN is WDD2210712A025336. Is the pdf document on this above quoted post applicable to my vehicle? If not where can I get it or can you help me with this, any advise/help would be appreciated.

Your right front air strut has a leak. Replace it and left side too as it will go soon too.

many cars have minor leaks and they drop a bit when parked for long periods, when driven regularly no one notices - but the air pump ends up working harder than it should - eventually the air pump gets less efficient - its supposed to reach 10 bar in 30 seconds of start up, but a lazy pump will only do 5 bar in 2 minutes - but that is still plenty of life for another 50 k miles of regular use even with a small leak. The issues tend to come if you start playing or loading the, car making it work for a living.

Like setting the ride height, especially if along the way you go full up or full down - this will often take a flexing seized level sensor and snap a few of the 4 legs that fix it to the car - with a sensor listing the heights start to get odd so you play more - that gets the pump working hard and the fuse pops.... no big deal as it shouldn't do anything in normal life - and may not even throw an error for months. But stick 3 big guys in the back and it can't compensate, then it will go strange and list, then balances itself out - but ends up lower all round - this usually causes it to throw a warning on the dash

a new relay and fuse is often enough to make the error vanish and get the lazy pump pumping again.... but if you don't tackle the level sensors within a thousand miles it snaps clean off and you get stuck - you can't drive it bottomed out - its too low and damages things and the air bags

Did not read this entire thread. But i have a 2012 CLS550 and everywhere i park is on a grade or hill. Nose is always uphill. I unknowingly bought this with leaking rear struts, so the trauma has been there since about a week after i owned it. Here and there I would see the front of the car on the ground and freak out. I'd then park it and let it sit and it was fine. Anyway - it would seem that the sequence is:

1. car is parked
2. door opens
3. door closes
4. lock the door

In this state the thing is always fine.
BUT
1. car is parked
2. door opens
3. door closes
4. lock the door
5. ( this is where it drops ) if the car is unlocked, and the door is opened / closed, the car then tries to level and the nose which is always higher in the air drops to the ground.

And I've recreated this. Just freaked out about it today and remembered that i had to grab something out of the car last night. Even knowing this, I still remain nervious as those front ones are like 1500 each.

If it sits for a long time, and it's cold it will lose air just the same as tires lose pressure. They last about 80,000 miles +/-
I hit a hidden pothole the other day and was ready to fight the entire world, i was moving from a stop, but you never want that with airmatic.
Although it's fine for semi' to hop curbs.

So seems the proper way to handle this is just drive your truck and let the thing rot in the garage so it doesn't break...
anyway - probably fine, just be mindful about the sequence with opening and closing the doors while parked.
The things just fart air any all the time when the key is in proximity - still don't know what that's actually doing.

otherwise, soapy water on the distribution block ( mine is behind the bumper ) - and then soapy water at the fittings under the hood ( super easy to get to )