This problem begins few days ago: not allways, but mostly, when i start the engine my power steering starts fully just after ~10 sek. I checked steering fluide and filled about 350ml. After that 2 days was everything ok, but then the same problem, but now steering fluide is full
Accumulator is ok, when engine on it shows ~14,6v

Any ideas whats wrong?

p.s. car Astra G 99' x20xev, power steering "delfi".