take the breaker bar and put it in the 3/8ths female slot on the tensioner. but instead of going clockwise to loosen it, go counter clockwise to tighten it while engine is running. if noise goes away, then good indicator that it is the tensioner spring that finally gave out..

this was a good feedback to me, hope it is to you. wish i would have thought about this before replacing water pump and water pump pulley and belt.