No noise when first started then 5 minutes later (when it's warmed up) when I rev it a little the noise sounds like it's coming from the plenum it kind of sounds like a baby crying each time I rev it "Waaa" or " Wann". No noise at idle, just when reved a little. I appreciate any help. Thank You.

 

Is this sort of a high pitched whine? If so it might be electrically related, such as an alternator. Does it get louder the higher you rev it up?