When I'm driving at 65 mph, I notice a whinning/squeeking noise on the left side of the engine compartment. If I let off the gas the noise goes away. I don't hear the noise any other time. I do notice that the pulley on the power steering pump does wobble. I don't experience any problems with the steering and I don't see any fluid leaking. What is the best way to see if the power steering pump is making the noise? The water pump and the power steering use the same belt so I can't isolate the power steering pump.