ive recently had a weird noise start to develop from the engine. its the sort of noise you hear when the car is on full lock, just like the power steering pump however i dont think its that as it even does it wen i dont turn the wheel, even sitting idling. the noise increases with the revs sounds like something is loose, doesnt sound majorly loud but seems to be getting more freguent especially when it rains. could it maybe be the power steering belt needing tightened. does the belt move even idling? l do know that the belt does need tighten as sometimes in the wet the power steering starts to jerk and go heavy but cud this be making the noise?? almost sounds like a knackered alternator bearing but without the whine, cant think of much else to descibe it. any help is appreciated