Strange suspension behaviour - w215

[Stratosurfer]

Hi, ok so on my CL500 The rear drivers corner sinks approx 1 inch when parked on my driveway, my driveway is on a slope and I reverse the car up it when I park.

When on level ground it's fine and sits the same as the other three corners so this consistently happens every time it's on my driveway either running or not it doesn't matter. I also conducted an experiment where Ive stopped on a steep hill and it's also sunk then when moved to level ground it corrects itself so it's not just my driveway. Makes me think it's a level sensor or body accelerometer sensor or something but having been hooked up to the local MB specialists star system no faults are present however he did say it wouldn't let him set height through the system and couldn't understand why.

The corner in question has a 'misted' strut (appears damp) but works perfectly ie raises and falls with the abc ride height control quickly, If I roll the car off my driveway and onto the road and get out to have a look it corrects itself. The MB specialist I took it to reckons the misting is nothing to do with it and still should work because of the constant feed but having said that it isn't leaking or is it? I'd have thought with the pressure involved if there was any leak at all it'd be a colossal one?

I recently fitted a set of height adjustable links to try to correct it myself but when I tried to raise the corner in question it raises the other side more? Not what I was expecting but that's what happened so it's left me a little baffled so back it went to the MB guy who set them but still the problem exists. He said to monitor it and let him know what it's doing.

To me it's the only corner with a misted strut so seems to me that's the obvious cause but MB guys reckons not.

Has anyone had a similar or exact problem as this?

 

[Mr Kripling]

Does it exhibit the problem when the engine is running? If not, then it's just the lock solenoid in the valve body wearing which lets fluid out of the strut when the pump isn't running. If the corner is drooping when the engine is running then I'd suggest an inspection using a SDS is the only way to go.

 

[Terry_]

I would suggest fluid and filter first

 

[Bellow]

Hi, ok so on my CL500 The rear drivers corner sinks approx 1 inch when parked on my driveway, my driveway is on a slope and I reverse the car up it when I park.

Were you to avoid using the handbrake (and 'park') by chocking the front wheels - would it still happen?

 

[Stratosurfer]

Does it exhibit the problem when the engine is running? If not, then it's just the lock solenoid in the valve body wearing which lets fluid out of the strut when the pump isn't running. If the corner is drooping when the engine is running then I'd suggest an inspection using a SDS is the only way to go.

Happens with engine running and if SDS means star diagnosis system then yes it's been on one but no faults.

 

[Stratosurfer]

Were you to avoid using the handbrake (and 'park') by chocking the front wheels - would it still happen?

I'll give that a try at the weekend but interested to know what that would prove?

 

[m2287]

The ride height might need calibrating on star... I had some strange issues with one corner of the car and the level sensor was just sticking a bit, disconnected it, moved the arm up and down and sprayed some wd40 on it and all was good after!!

 

[Stratosurfer]

The ride height might need calibrating on star... I had some strange issues with one corner of the car and the level sensor was just sticking a bit, disconnected it, moved the arm up and down and sprayed some wd40 on it and all was good after!!

It's actually got a new sensor on it and when on star the ride height values were set but it wouldn't let him ok it to move onto the next page (if you know what I mean).

I might also try swapping sensors with the other side and see what happens then which leads me onto this next obvious question..

Are all the ride height sensors the same or are they sided?

 

[m2287]

I've had two misting rear struts and they did have to be replaced but it didn't come up with any errors or sagging, you could feel the car wasn't riding right, in the end it was the internal bottom bump stops that had cracked on both of them (at seperate times!!).

Does your car sink instantly on that corner when it's turned off or gradually over Afew hours?

Not sure if the height sensors are all the same or not tbh!!

 

[Bellow]

I'll give that a try at the weekend but interested to know what that would prove?

Give it a go and report back. It's a longshot but, my car does exactly the same - and it has neither air or hydraulic suspension....

Does your car sink instantly on that corner when it's turned off or gradually over Afew hours?

If the answer to the above is 'instantly' - then my longshot theory may be correct.