Alright I am into this with a new tensioner pulley and a new alternator with no changes. I got a stethoscope and can't really isolate anything except that its cyclic and high pitched in the area of the tensioner on the main belt. Take belt off no noise. Take supercharger belt off same noise. The metallic squeak is only heard when the car is cold or engine is not up to temp. It can be 90 degrees and it will squeak if the engine is cold. As soon as its up to operating temp it quits. The car has a ~6mo old remanned power steering pump and a new water pump.
Please help me figure this out? Could the tensioner lever motion be doing it? New tensioner?