cavallera2000

Hello all,

I am the proud owner of a ML420 CDI 2007 with airmatic suspension. I bought the car used in 2013 from an authorized used car reseller in Germany with close to 90000km. Not long after buying did I start having problems with the air suspensions. Not to bore you, until now I have changed the front-right air suspension about 5-6 times and they keep malfunctioning due to leakage. About a year ago I read in one of your threads I think it was, that the problem must be in the central air compressor, which generates too much pressure. I told that to the car mechanic where I took but they can only go by what the diagnostic tool tells them and they cannot do anything but that...
Now I have a bunch of other problems with it, which, I suspect are related: the car's ESP switches on all the time for no apparent reason at the tiniest turn, or when the road surface isn't smooth or flat. Moreover, the ABS is kicking in at the smallest braking!
Furthermore the suspensions are hissing like crazy when I switch off the engine (more than usual) and the car is staying uneven, titled on one side. There is no indication of any error, the mechanic who scanned it with the diagnostic tool it didn't give him any wheel sensor error just an error of the "electric valve", which he reset to see if it reappeared but it never did...
So now I don't know what to do, the car obviously is having serious problems to the point where it is dangerous to drive; on the other hand the diagnostic tool doesn't show an error, so the mechanic can't do anything about it!

Please help!

Alex

zemun1234

I am dealing with similar problem with AIRMATIC. As first step, you need diagnose car with STAR device (designed for Mercedes) with developer mode activated. You can get all kind of testing including testing for each air spring or other details.
In example, I have problem that air compressor cannot build enough pressure (16 bars - only 8,9 bars) and it cause that I get signal on my dashboard. Purchased air compressor and I am going replace it next week probably.

Russell Ormerod

Explain how the airmatic fails? Your description is too vague.
Did the bags burst?
Were the front bags replaced with or without changing the shocks?
It's a simple system, just find another mechanic who knows how to test
It properly

bilagain

Get a water spray bottle and make a mix of dish soap and water and spray the tops of the air bag suspension and the air line connector. Make it good and wet. Give it time but watch for air bubbles. Our R500 had similar issues and it was the fronts. I tried a new pump and the control valve unit because I didn't want to believe the bags had gone bad.

Some release of air pressure after you've driven the car is normal, more like a blast of air hissss. That is the system trying to clean out the air intake filter.

Try the soapy water. Get it wet and give it time. Mine showed in a few minutes. You may need to run your car so it tries to stay level.