Thanks PazoWell AG129,
Opposite to your upper encircled "S" is a grub screw with 3 mm allen head. In this channel there is one of the three check-valves the sliding valve actuates. This specific S-channel valve provides oil pressure for the height control rods, front & rear. My hypothesis is that you could have dirt/sludge in this valve. It cannot be disassembled but you can try move the check-valve by pressing with thin wire from both sides until the valve moves freely, maybe 1-2 mm. Sorry to say, to do this you must disassemble your ADS1 main control valve.
See also Jon Bearpark's drawing in this thread. Also, see this picture.
Hope I managed to clarify…?
Yes that does make things more clear for me to understand. Unfortunately I won't be able to tackle this until next Thursday. So I have a week to study the old spares I got and hope when I take my unit apart that it finally works out as intended.
Manhunt, yeah I watched those videos of Citroens running around on three wheels or changing tires without a tire jack, very impressive. I do understand their ADS is tuned for a very different purpose.
I realized that with time the comfort mode is becoming slightly more forgiving or comfortable if that makes sense. Yes now the difference between comfort and sport is very noticeable, maybe the car needed to be driven around some more to self-bleed.
I have the AMG monoblocks with:
245/40-18 Michelin PS4 on 8 inch et31 wheels in the front and 20mm H&R spacers bringing my offset down to et11
275/35-18 Michelin PS4 on 9 inch et35 wheels in the back with 25mm H&R spacers bringing my offset down to et10
The spacers are a bit aggressive and require fender rolling, but the widened track actually made a difference to handling a bit even before restoring ADS
With ADS on sport, the car feels so planted and it keeps pushing you to try and find the limit of grip. I love how the car feels on sport mode.
On comfort mode the car is much more lenient and allows more body roll and generally makes you feel less bumps on the road but only to a certain extent. As you said, I think comfort mode would work best with the original 16 inch wheels with big sidewalls.
Too bad we can't drive on three wheels like the Citroen 😋