Borrow a pressure tester and pressurize the system so it doesn't have to be hot. Then get lots of light and a good inspection mirror (the flexible kind on the long shaft). I'm with POS, no reason to start yanking stuff apart until you know what you're dealing with.

Another suggestion: clean that area of the engine thoroughly. After it's dry, toss some talcum powder back there; use a dry sponge to pick it up, the pat it onto all of the surfaces. Then pressurize the system. It will be lots easier to follow the trail that way.

Good luck.