i have an 2.8 quattro and have had a slight encounter with a tree on the front, in doing so broke the resivoir for the power stearing and have to replace this but in doing so lost the oil in the stystem, i repleced the oil and since then had this knocking sound when turning both ways, i did get lots of air in the resivoir and before the stearing wheel was straight when the wheels were straight, but now the stearing wheel seems to be pointing left as if i was in a slight turn when the wheels are straight. could there still be air in the stearing and how do i get it out??????or do i need the play taken out???????has passed an m.o.t since then. any help on this matter would be great as i dont feel safe with the kids in the car.