Mercedes Benz part number 1293200058 or 1293200858, aka A1293200058 or A1293200858, aka A129 320 00 58 or A129 320 08 58.
This valve mounts to the distributor p/n 1293270189, which is oftentimes mistaken as the failing part with the assumption that the valve is part of the distributor.

The ADS valve is located near the right front wheel. The valve is attached to the distributor above it with four bolts, and it is easily removed - please do not send it with the distributor. Ideally, have the car on a lift with all four wheels up in the air when you remove the valve, in order to depressurize the ADS suspension system.

PLEASE resist the urge to open up the valve or to fix it yourself. Most folks damage the valve significantly when they try to take it apart, and there may be a surcharge for replacing metal parts with our service. Do not over-tighten the pressure relief valve on the outside (hex bolt), or you may damage your ADS valve beyond repair. If you severely damage the two plugs on the side (the ones with two holes in each, which make them so tempting to try and unscrew), then you're sunk.

As part of the service, and without surcharge, we will replace some metal parts as needed, such as ball bearings or springs inside. We will also polish out blemishes inside, re-shape the pressure relief valve, and re-lap the pressure relief valve seat as far as possible (for those who have over-tightened the valve a little). We cannot replace the governor rod, or the solenoids on Euro versions, or the plugs on the side (because they have valves in them).

We replace and upgrade over a dozen seals (about two dozen on the Euro version), and we clean out carbonization and deposits. We also check and adjust the tension on internal check valves. We use edge-activated seals of our own design to seal the plugs on the side.

Please prepay your order and send in the valve for rebuild service.