I was repairing my o2 sensor wire at my school and when I went to pull out of the bay my power steering was almost gone. I say almost because its not as hard to turn it as the engine is off. So what could have happened? I took it on the freeway today and it felt normal but when I got off it was hard again. Is my pump about to die completly? The fluid is full and the belt is tight. Any help is greatly appreciated.