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My '14 E550 seems to be dropping the right, rear a bit and raising the left, rear overnight. If two fingers between the tire and body is normal (the fronts appear to never move), the LR raises to 4 fingers and the RR drops to 1 finger. There appear to be random, short 'psssst' bursts from the LR shortly after getting out of the car, and for hours later, too.
Conditions are ~70-80F during the day and ~50-60F in the evenings right now in the Northeast.
I will try the raised mode next to see what happens, but it's going in to the dealer on Monday to have a couple things checked out, including this. The car is new-to-me so I'm trying to calibrate what is "normal" for this car. (This does not seem normal). Will report the dealer findings after the visit.
The dealer did a re-calibration and after a week of observation, it is sitting more evenly. It's not perfect (<cough>OCD<cough>), but it is much better. Luckily, it seems, an easy fix for my issue.
There are many strings about AirMatic so I picked one.
Here is the problem:
If I leave my car on Sports setting the car is all down in the next morning. All corners all the way down. Comes up fine when car starts.
If I leave it on Comfort setting it does not do this even when it sits undriven for 4 - 5 full days at an airport parking lot that happens 3 times a month.
I have purposely tested this for 6 times and every time I leave it on Sports the car goes all the way down over night but has not done it once when I leave it in Comfort mode.
Some could argue Comfort mode has more air and it takes longer to leak out from bags.
Well,
- All four bags do not go bad at the same time
- Comfort mode is only about an inch higher than sports so it increases air amount in the springs only slightly and does not explain why car does not drop when left in Comfort mode.
- If it was about air amount in the springs the car would have to be 4 times higher in Comfort mode to be able to maintain air in bags with the same leak rate to have some left after 4 days.
The facts for me tells my air springs are not leaking nor can it be a leak in the valve block since the car stays up in Comfort mode.
So, my attention has turned in the level sensor reading and what they should read when the car is shut down and locked and the car lowers down to the set resting position.
Does anybody have info what the Sports mode level should be vs. what the Comfort level should be?
My thinking is that the level sensors are telling the car is higher than it really is and this is why it drops all the way down.
I have the iCarsoft scanner and I can read the level sensors but would need to know what the readings should be when the car is resting.
Exact symptoms I had. Your front air strut (at least one or possibly both) is dry rotted at the base where the bag is attached to the shock body via the metal collar, see image below. When the car is in raised mode or comfort mode, the way the bellow folds over itself and it creates an airtight seal over the cracked area thus preventing the air from leaking out. When you have it in sport mode, the fold over no longer occurs over the cracked area and depending on air temperatures and humidity (rubber swells), it will allow air to escape past the fold.
The reason that both sides go down is because the system is programmed to equalize the pressure between the front bags (up to a point) so that the entire weight of the front vehicle is not resting on one air sprint. This equalization is done by the distribution block under the rear bumper. Also remember that the system is sealed not at the valve block, but rather at the pressure relief valve within the compressor, so if the system is not leaktight at some other point before the pressure relief valve you, could have air escape from any air spring through the valve block and then out the faulty bag.So yes, one leaking spring can let air out from any spring, though it would have to be a large leake for it to get past the distribution block, which again only distributes the air, and is not responsible for complete airtightness to each spring, Only the pressure relief valve seals the system and that is past the valve block, inside the compressor.
Don't be in denial like I was and start throwing the cheaper parts (like level sensor and distribution block) at the problem instead of admitting that the air strut might be bad. There is a simple way to 100% confirm;
Jack the front of the car up on both sides and put it on jack stands. Remove the front wheels. Pull up air spring skirt. Undo air line at the top of the strut. Let is FULLY air out. Pull up air bellow and check for cracking where the rubber meets the metal collar. This is 99% of the time where they always leak because of the extreme bend the rubber has to make when it folds over.
As you can see in the image below, unless you fully air the bag out, you cannot see the cracks on the bags because it;s still folded over.
Lastly, put the car back on the ground by jacking it up from the CENTER jack pad on the cross member under the engine. The jack will get stuck underneath it because car will be too low. Turn the car on, but do note that the car will not be able to fully fill the bags with one cycle because the pump will shut off after 45 seconds or so to save itself from overheating, you will have only half way inflated bags and the jack may still be stuck under the car. With the car still running be patient and wait it out until the pump cools off again, probably in about 3-5 minutes depending on ambient temps, the pump will kick back on again by itself and then fully fill the bags, at which point you will be able to take the jack out.
This is kind of the gist of it. Your air spring is leaking right at the base, but the fold over is keeping the air in still. Depending on where the fold over occurs, it may or may not seal, however it was never designed to seal a leak, it's just a mear coincidence that it does.
This is kind of the gist of it. Your air spring is leaking right at the base, but the fold over is keeping the air in still. Depending on where the fold over occurs, it may or may not seal, however it was never designed to seal a leak, it's just a mear coincidence that it does.
Thanks for your very detailed post. I will look into this and it may very well be that after 10 years the air springs have dry rotted like you say, but also the read drops and those are only about 5-6 years old. When I had a problem with rear springs the leak did not make the whole rear go down. Of course the non-leaking side also lowered but it was easy to see which spring is leaking. This case was with bad spring design and both sides were replaced with a better design spring.
My car goes down all corners completely if I leave it on sports and I have hard time to believe this is due to the leak but you could be right. I'll look into this by your instructions.
I’m having the same problems with my E550 as everyone else. I can handle some easier repairs myself, but this seems to be beyond my capabilities. Can anyone recommend a good/honest shop in SoCal that knows what they’re doing regarding this exact problem? I don’t want to get screwed and start paying thousands of dollars without actually solving the problem.
where in socal? I'm pretty much an expert now on W212 airmatic and I also have the Star Diagnositc computer. I'm in San Fernando valley
It looks like all 4 wheels are on the ground, it;s highly unlikely that multiple bags would leak at once. I'm suspecting either distribution valve block, pressure relief valve or level sensors, on top of probably a leaking bag as well. I have a spare good knows of all of those along with a spare compressor..
Excellent! I’m only about an hour from you off the 210 east! That would be fantastic if we could coordinate getting this fixed up. I will message you directly. Thank you.
Last edited by Pantheon17; 02-26-2020 at 02:50 PM.
I’m having the same problems with my E550 as everyone else. I can handle some easier repairs myself, but this seems to be beyond my capabilities. Can anyone recommend a good/honest shop in SoCal that knows what they’re doing regarding this exact problem? I don’t want to get screwed and start paying thousands of dollars without actually solving the problem.
If you are at all a DYI person the job is very easy.
where in socal? I'm pretty much an expert now on W212 airmatic and I also have the Star Diagnositc computer. I'm in San Fernando valley
It looks like all 4 wheels are on the ground, it;s highly unlikely that multiple bags would leak at once. I'm suspecting either distribution valve block, pressure relief valve or level sensors, on top of probably a leaking bag as well. I have a spare good knows of all of those along with a spare compressor..
hey guys, so been struggling with my friends 2010 E550 airmatic suspension. He had issues with malfunction light coming on for a while but as of last few weeks his rear air springs dropped completely but would pump back up after raising the suspension (pushing the lift button). Anyhow he drove on it one day when it was completely bottomed out(bad bad idea ofcourse) He brought it to me and since I work on cars I started with checking compressor and valve block and ofcourse rear air springs. Compressor was cooked, valve bLock leaking and both rear springs were shot. So I replaced them all along with the airmatic compressor relay and yet the rear suspension stays completely down. I manually filled it with my autel but seems to not work or raise up. Since you mentioned you are master at this can you give me at input ? I'm unable to calibrate as the compressor clocks out within 45 seconds from heat sensor. Yet rear end does not lift. Seems to fill air in the bags but something tells me the ride height sensors went bad? Do note he drove on it for a while with rear end slammed. Any help is appreciated. Thanks!
hi, I facing the same errors and issue of lowering my car overnight at sport mode for my ‘16, E400. What you did or replace to resolve this issue? Thanks in advance.
Originally Posted by - Mover -
I managed to find a scanner for the car. Very nice guy scanned it for me. Hopefully I could return the favour.
Two codes existed for the suspension. C156784 - The left front vehicle level is outside the tolerance. There is a signal below the permissible limit value.. C156984 - The right front vehicle level is outside the tolerance. There is a signal below the permissible limit value,
I'm not sure if these code are telling me what I see (the car is sitting low in the front end). Obviously, the system is going to realize the car is sitting to low when I start it up. So these codes are telling me something I already see. Not much news here.
hi, I facing the same errors and issue of lowering my car overnight at sport mode for my ‘16, E400. What you did or replace to resolve this issue? Thanks in advance.
the answer is literally this this thread, just need to scroll up. Here, to save you the scroll the answer is; your front airbags are leaking at the seams, you need new complete front air struts.
the answer is literally this this thread, just need to scroll up. Here, to save you the scroll the answer is; your front airbags are leaking at the seams, you need new complete front air struts.
thanks for prompt response, I saw a lot of article of malfunction of airmatic sensors? Is this possible, especillay my car mileage is only 90,000km? And did not go down on comfort mode? And recently scanned and got the attached error?
mileage is not the issue, my car had 45k miles when the struts started leaking. It;s more of an age and climate thing. I'm in California where we have very dry and hot climate and the rubber deteriorates pretty fast. My original struts lasted from 2011 to 2018, so about 7 years. I exprect the replacement struts to last around the same amount, maybe a little longer now that I park my car in a climate controlled garage.
The error code you post just shows the car is too low, nothing more.
If you scroll up you can see how to check if your air struts are dry rotted, not very hard to do.
06-17-2018, 02:56 PM
