To prevent boredom setting in,

[robmc52]

The car has decided to keep me occupied. It's parked facing downhill in the pic, when I left it yesterday it was sitting level. Overnight the back end has raised itself up.



The day before it was parked facing uphill and the same thing happened. If I take it for a run it resets to the normal height, and works as it should. Any pointers would be appreciated!

 

[robmc52]

Well it seems I'm on my own with this one. Internet research suggests the problem is a solenoid sticking open in the valve block, pressurising the strut when the car is not running. So one of these


has arrived today. WIS states that all four struts should be extended when re-pressurising the system, so I will be carefully jacking the car up onto axle stands tomorrow

 

[Wighty]

Well it seems I'm on my own with this one. Internet research suggests the problem is a solenoid sticking open in the valve block, pressurising the strut when the car is not running. So one of these

View attachment 57555
has arrived today. WIS states that all four struts should be extended when re-pressurising the system, so I will be carefully jacking the car up onto axle stands tomorrow

I think member @flowrider had a big info sheet/internet link to all things ABC last week (apologies if it wasn’t him)

 

[robmc52]

Just Airmatic on mine Wighty, the S Class Encyclopedia has some useful info on it https://w220.ee/Airmatic#Level_Control_Valve_Unit_.28Y36.2F6.29
The new one is a cheap Chinese job, so I'm thinking of getting a set of seals and rebuilding the original as a spare, not much else to do at the moment!

 

[robmc52]

Well that didn't go as expected, got the car up on axle stands, replaced valve body, compressor doesn't run, so no pressure in system. I've kept the struts fully extended throughout, so was expecting the pump to fill the system when starting the engine, and to then gradually lower the car back down off the stands. Just to make sure the new valve body wasn't duff, I put the old one back in, still nothing. Should I have disconnected the battery, perhaps something needs resetting

 

[alexanderfoti]

If the car is up in the air, it wont run the pump. It sees the ride height is too high, so opens the valves.

Have you tried lowering it onto the suspension whilst the engine is running?

 

[robmc52]

Thanks Alex, that's got it working.