This is the message that I've posted before:
I currently own 95 SL600 with air struts . I have a problem with a rear suspension. When the car is in off possition and I test the shocks (by pushing the car down) it goes right back up, which means that the shocks are good. Now I've tried doing the same thing when I stared the car and the result was the same, i would actually say that it was even stiffer. When I drive the car and I hit the bump, only my rear bouces back very badly and it seems like that the shocks are bad, but this car has an air suspension and I do not know how it operates. How can I solve this problem? What needs to be changed: air struts or accumulator lemforder (has to do with air suspension). Somone has told me that it's a known problem, but i need the answer how to resolve this issue.
Please help.
Thank you
Steven

Just now I spoke to my mechanic and he is telling me that ADS valve ($950) is leaking and needs to be replaced. I personally saw it with my eyes that it's leaking, but is it possible that all the problems are caused by it? What is the possibility????

PLease let me know your opinion, and how many of you replaced this ADS valve.

The sl600 does not have air suspension. It has a variable stiffness hydro-pnuematic system. There are nitrogen charged 'accumulators' for each wheel that provide the 'give'. Thus far it's just like the rear shock system on 560 model 126's. (These accumulators cost about $120 each and are the green spherical double fist sized steel balls in the trunk and in the front fender wells. When those get low in nitrogen, the car rides very hard.

The added wrinkle is the ADS - Active Dampening System, which adjusts the shock stiffness (by controlling th eflow of oil from the shock to/from the accumulators to best control the bumps and keep the tires on the road. There are acceleration sensors front and rear to sense body movements and the electronics adjust each shock to keep the car smooth. There is a switch on the console which allows you to set them to a 'sportier' (stiffer) setting.

It sounds like your rear shocks do not have any oil in them. Have you checked the hydraulic oil reservoir?

If the ADS valve is leaking badly, if may have to be replaced. You might first see if replacement seals are available. It could be the rear valve has failed completly open, which would allow the rear end to 'bouncy bouncy'