Vacuum leak like a mofo

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new guy here fellas.
New 4.7 installed in December. After break in, it developed a vacuum leak. Once warm it will get to going and it sounds like a jet engine. It's LOUD. Its loud enough I can't even tell which side of the motor it's coming from, but as best I cant tell, it's coming from the driver's side. I've attempted to get it back to Jeep Masters while it's going off. but it manages to whine itself out before I can ever make it over there (probably five attempts so far). After about 10 miles or so, the scream just dries up and poops out, normal Banks rumble is all that's left. The obvious fix is to leave it with them over night, but it's my DD and I don't have vacation until May.
Sorry, didn't realize I just left that there like I was whining.
I don't have the first clue how to troubleshoot a vacuum leak to conclusion. Although, as bad as this one is, it shouldn't be too hard. Can anyone point me in some kind of direction to even get started?

[nicpaige]

Are you sure it is a vacuum leak and not a whistle from your air intake system? New throttle body perhaps? I moved my air intake into the cowl and have a bored out throttle body and it sounds like a high pitched whistle, just haven't got around to working on it yet.

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No Nic, I don't know, but I'm less inclined to think so. It doesn't change pitch with RPMs, it's a static pitch that is either on or off. If on, I can have the jeep in the driveway running and I can hear the issue inside the house. - jeff

[Russ Pottenger]

How does it respond when you gradually start to restrict air entering the throttlebody?

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I'll have to give that a go, and let y'all know.
Unless there's better method, I'll drape a plastic bag over my K&N slowly covering more and more surface area. I need to clean it anyway, may just take it off and put limits on the tube. - jeff