coupe q hydaulic problem any BTDT?

[DFAUTOHAUS@aol.com]

Hello all
Got a friend with a problem that seems unique that I havent seen before, so 
may one of you has. 
He's needed a p/s pump for some time and finally replaced it along with the 
accumulator. He now still has some back pressue that forces fluid out the 
reservoir cap. Not a great deal and seems to only happen when brakes or 
steering assist is used (not at idle or revved up while motionless) . 
If anyone has an idea, it will be appreciated.
tia
DF
95.5 S6 wagon
91 200 tq