my power steering pump
 

I have a 92 Nissan Maxima and something is wrong with the power steering. at first it was leaking power steering fluid from the hose, so i changed the hose and now its hard to turn the steering wheel. its fine while im driving fast, but when im on the brakes or just going slow its really hard to turn. theres a piece with a spring that fell out of the pump that i may have put back in wrong but im not sure of the correct way to put it in. please help if you can.