Back in the winter my power steering became very stiff, when revving the engine A LOT it would make it better for about 5 minutes. Then the temperatures got better and it stopped. Last week a strange hissing/rasping noise started from one of the pulleys on the aux belt, I'm 80% sure it's from the water pump, it starts after about 2 minutes after the engine is running and turns to a constant hiss when driving fast, when driving straight with my foot down on the clutch the sound subsides, then reappears when brought back up again. The power steering is again heavy! So is it the auto tensioner at fault, the power steering pump or the water pump, or all of them? Took it to kwik fit who said it may be the power steering pump but might not be, he also said that the belt is in good condition.. Any ideas?