[5potnoodle]

BTDT. Presuming that you have used the correct Audi hydraulic fluid (important) and bled the system correctly (also important) after changing the pump then I would think you need your spheres replacing I'm afraid. The suspension will sag when parked for any length of time as the pressure in the system drops so that's quite normal. The spheres contain nitrogen seperated from the hydraulic fluid by a membrane, this acts as the damper in your system. When the membrane leaks the nitrogen, you have no damping and your suspension is bouncing up and down on the springs, just like when a normal shock absorber stops damping. The suspension will still rise and fall because of the hydraulic fluid being pumped into the system.

In theory, it should be possible to recharge the nitrogen spheres with some modification to the sphere itself. I've seen on the web a mod for the brake sphere which involved fitting a car tyre type valve to it so it should be possible for the suspension spheres too I'd have thought. Might be best to go see a friendly Citroen expert to see what they can suggest.