To see if it's the water pump, take off the serpentine belt when the engine is cold. The t-stat does not open for the first minute or so any way. Start and run engine. If the noise stops, then it could be the pump or another pulley, but you now know where to look. The pump on partsgeek.com is $131.75 and that was the first place I looked. I have bought from them before and you can get another 10% off by just asking---I have done it. Good luck Jimmy