That post is about the EHA (electro-hydraulic actuator, I think that was it's full name). It is the black box connected on the side of the fuel distributor. Hope this helps

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190E 3.0-24v (M104 980) turbo @ 0.8 bar
1/4 mile: 2.483 / 13.540 / 175.17 km/h (street tires)