How do i push piston in rear caliper back ?

[thyrsted@olsy.dk (Kenn Thyrsted Nielsen)]

Hi.

As it is time to change the pads, i set my mind in doing it this evening. -
But...

Trying to force the piston back in the caliper, i found that it is
virtiually impossible.
Even when applying a large ammount of "near violence" nothing happened.

Having changed pads myself on my older non-Q and non 200 Audis, i never had
to use this much force.

As there isn't any sign of malfunction; braking is okay, pads is just worn,
i wonder if there is some sort of valve that makes it nessecary to bleed the
brake in order to make room for the new pads ?

TIA

Kenn
'87 200TQ Avant