On my my03 wagon I find that some mornings when I get in the car to go to work I have no power steering for the first couple of turns on the wheel.

I park on a bit of a hill with the car facing down it and would turn the wheel to the left to get out of the parking space and then back to the right to straighten up for the road and it is towards the end of this second turn of the wheel that the assistance kicks in and all is well again.

Doesnt do it all the time though, only happens in a morning at my house and I have checked the fluid level and thats ok.