[David N.]

Thanks for the reply CJ, I feel a bit less worried now.

I took off the engine compartment lid, revved it a bit. Looks like it is definitely an air leak, sounds like it's coming from inside the intake manifold, perhaps around the resonance flap. It's a rushing of air that definitely increases with throttle. It echos around the manifold so I can't really isolate it any more than that.

The guy that was helping me saw the bracketed seals around the manifold center pipes were loose so we tightened those, but didn't affect the air rushing sound. I have no idea how to get any more specific about where the leak is coming from.

Anyone want to venture guesses? Is the resonance flap seal known to go bad? Is that pretty much the only valve in the intake manifold that would be a possibility?

-David