I have a noise that sounds to me like a stuffed alternator or PS bearing, but its more mid or rear of motor. Its only noisy in vacuum or boost, which makes me think its a whistle caused by a manifold leak, but its very loud for that. I've checked the boost controller/FPR connections and it all looks ok. The noise is not affected by moving the tubes, so i guess that means its not a leak there. The plenum was off about 3 months ago but its been fine until now, and the top row of nuts are still tight.
Any ideas?