I've been suspecting a vacuum leak for some time (rough idle, surging, idle rpm's varying widely). I have examined the vacuum lines many times, and could never find a leak. Today I figured it out. On the back of the intake there are three connectors, and I had vacuum lines going to two of the three. The other connector was open, with no cap or plug on it. I was sucking air (and a lot of it) all the time. Ahhhhhhhhh, such a feeling of accomplishment when I finally found that.
