Originally Posted by Joe-
Hard to say without the car in front of me, remove the belt tand slowly turn the pulleys to look for any play. Could also just be the belt being worn and not tight enough or if you just recently replaced the belts, maybe the tensioner was over tighten.
Oh you're talking about the main belt? Wouldn't it make a noise at all RPM's though? It only happens with the car at around 1000-1200 RPM otherwise it sounds normal. So it's definitely not the waterpump, right? I've been watching my water temp on the fuel gauge and it's been around 1/4 all night even when I pushed the car a bit.