Yep, my vote goes toward a vacuum leak. I did have a similar problem one time when the maf became dis-connected, but I'm sure Contourgirl would have noticed if that was the problem.
95 Contour Zetec, ATX (wrecked, sitting in the barn)
95 Mystique Zetec, MTX
2000 Taurus SEL 3.0L Duratec
1994 Crown Victoria LX 4.6 V8
1993 Chevy Silverado 4.3 V6
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