One corner collapses 30 minutes after car turned off, strut replaced but didn’t work
Thread Starter
Junior Member
Joined: Aug 2016
Posts: 59
Likes: 18
2011 S550 4Matic
One corner collapses 30 minutes after car turned off, strut replaced but didn’t work
My front left strut collapses completely every time I turn the car off. It’s a slow deflate that takes around 15-30 minutes and happens every time I park. I replaced the strut but the behavior is the same.
where should I look next? Air lines? Valve body?
my concern is that I thought these struts had a residual pressure relief valve at the top that stopped it from leaking if the incoming pressure dropped. If this is true, then a leaking strut is just that...
where should I look next? Air lines? Valve body?
my concern is that I thought these struts had a residual pressure relief valve at the top that stopped it from leaking if the incoming pressure dropped. If this is true, then a leaking strut is just that...
Thread Starter
Junior Member
Joined: Aug 2016
Posts: 59
Likes: 18
2011 S550 4Matic
A bit more detail on the car's behavior:
I ran the car for about 5 minutes and it doesn't seem to be leveling itself properly. The level sensors report -1 inch at the front left and +1.6 inches at the front right. The level sensors appear fine and seem to be reporting the true height at each wheel. I suspect the level control unit (valve block) but I'd expect an error code if the solenoids were failing/leaking.
One other odd thing is that the pressure sensor only reported 1.24 bar after the car had been running for a few minutes, this seems oddly low. I thought the struts held 5-10 bar.
Any advice would be greatly appreciated! I'm dangerously close to taking it to the dealer...
I ran the car for about 5 minutes and it doesn't seem to be leveling itself properly. The level sensors report -1 inch at the front left and +1.6 inches at the front right. The level sensors appear fine and seem to be reporting the true height at each wheel. I suspect the level control unit (valve block) but I'd expect an error code if the solenoids were failing/leaking.
One other odd thing is that the pressure sensor only reported 1.24 bar after the car had been running for a few minutes, this seems oddly low. I thought the struts held 5-10 bar.
Any advice would be greatly appreciated! I'm dangerously close to taking it to the dealer...
Thread Starter
Junior Member
Joined: Aug 2016
Posts: 59
Likes: 18
2011 S550 4Matic
[ SOLVED ]
I replaced the valve body and at the same time fixed a small crack that had formed where one of the lines entered the fitting at the valve body. With these two repairs completed, the air suspension functions normally.
