If you have access to a boost gauge you can temporarily bypass all that stuff and go straight from manifold to alda and see what kind off pressure that turbo is making. Thats where i would start first thing to see is if its functioning and making pressure. If there is no boost even at wide open throttle in second then you have some sort of wastegate failure or lack of fueling. Are you absolutely sure this noise is coming from the turbo? Worn injectors leaky DVs and and bad timing also make a clattery knocking noise.