S213 E220d rear airmatic issue. Sitting low overnight or when engine off

[dn95]

So my s213 had around 135k miles when I got this issue. My rear suspension (rear only has airmatic) started sitting very low sometimes (few time a week) when left overnight of engine of car locked. After engine start up, it would come back up slowly and would be fine.

Local garage said specialist or main dealer can only work on it.

Took to mb specialist and explained. They found a fault that couldn't be cleared in the suspension control module. So they replaced that and was good to go. Few days later, same thing happened. Took it back and they said they needed to adjust the start ride height lol. They done that and again, same issue after 1 week or 2. Took it back again and they explained they checked all suspension parts and was all good. Only thing they "suggested" was to change the valve block, even though it was a good part but they said thats they only place that they can think the air can leak from. So they did. Was ok for about 1 month

They did say from seeing the car the first time that there were zero air leaks. They even had the car overnight one time.


Now its happening again (and unusually, it sat low after the valve block replacement, when it hit below 0 degrees, I dunno) so i said let me change the battery because its been 5yrs and ive ben getting a battery warning for sometime. I did and its still sitting low few times a week.


No one can find the issue, if you guys have any experience with this pls help. Or I might have to do a coil over suspension conversion in the rear or live with the issue but im already £1k in the hole, I'd prefer to get this fixed

 

[Dickster]

I assume the system uses airbags like my BMW X5. My X5 has the same issue but only on one side. The other side has a fairly new air bag - it split. In hindsight I should have replaced both.

My garage couldn’t find any leaks either. However, I have read that it can be the air bag or valve block. So, mine is having the airbag replaced on Tuesday and if that fails the valve block - both are fairly cheap to replace.

If that doesn’t fix it I’ll buy conventional springs …..

 

[Will]

Faulty air bags can cause this issue. They’re a consumable item and wouldn’t be unusual to replace those at this age/mileage.

It’s a simple system, it just needs patience to work on.

The air has to be leaking out from somewhere.

Try another specialist perhaps if you’re not confident in the diagnosis. Better to get it fixed sooner rather than later as you’ll end up wearing the compressor out as it tries to pump up all that lost air each morning and overworks as a result.

 

[Weds]

I would say your 'MB specialist' are hardly a specialist at all. Just search the forum, rear suspension leaks are a common occurrence. On the 212 air lines frequently fail due to the lines rubbing on the chassis (mine did) and I suspect your 213 is probably the same. Checking for leaks with soapy water doesn't always show up anything (mine didn't) I firstly changed the airbags and as that didn't cure it I changed the air lines. It's been fine since.

Changing the air lines are the cheaper option. Find a more capable Indy...

 

[Benz17]

There are so many post about ‘My MB specialists’ but these specialists don’t know how to fix certain issues.

 

[GeorgeR]

So my s213 had around 135k miles when I got this issue. My rear suspension (rear only has airmatic) started sitting very low sometimes (few time a week) when left overnight of engine of car locked. After engine start up, it would come back up slowly and would be fine.

Local garage said specialist or main dealer can only work on it.

Took to mb specialist and explained. They found a fault that couldn't be cleared in the suspension control module. So they replaced that and was good to go. Few days later, same thing happened. Took it back and they said they needed to adjust the start ride height lol. They done that and again, same issue after 1 week or 2. Took it back again and they explained they checked all suspension parts and was all good. Only thing they "suggested" was to change the valve block, even though it was a good part but they said thats they only place that they can think the air can leak from. So they did. Was ok for about 1 month

They did say from seeing the car the first time that there were zero air leaks. They even had the car overnight one time.


Now its happening again (and unusually, it sat low after the valve block replacement, when it hit below 0 degrees, I dunno) so i said let me change the battery because its been 5yrs and ive ben getting a battery warning for sometime. I did and its still sitting low few times a week.


No one can find the issue, if you guys have any experience with this pls help. Or I might have to do a coil over suspension conversion in the rear or live with the issue but im already £1k in the hole, I'd prefer to get this fixed

I have had the same misery with an s212. (Main dealer, then independent ones, 3 failures in total 100k mil - 170k mil)
The point is:
The MB airbags do not last too long. (60k - 100k mils). When those go you will see the lowering time to time but not always (a small leak allowing the air to go out depending on the actual position). If you do not have them repaired they will come more and more frequently, nearly always. The worst comes when the hole (crack, etc) gets so big that the pump cannot keep up and your car will stay in this lowered position on a motorway.

If the lowering is uneven (one-sided at least a bit) then it is highly likely that it is the bag. It is an easy job net 1.5 hrs (gross max 3hrs) of work + price of the part: £250-600, (depending on where you get it: MB @ main dealer - MB @ from web - aftermarket. MB does not prove to be better than the aftermarket. Even so I went with the MB OEM all the time.)
With some luck, it is only the pipe between the bag and the pump. (Even so, it is worth buying the air spring as you will need it sooner or later.)
A "proper" workshop will do a levelling via software once the bag or any item has been replaced. You need to remind them and it costs them nothing so they may not charge you.
The valve block is far more stable than the bags and the pipes. The pump has overload protection so it is less likely to go away with a leaking system.
I have played with the conversion myself but decided to stay on air finally.