2001 Ford Taurus seems like its stuck in neutral

My wife was driving the car then stopped at a stop sign and when she went to take off the engine just revved. Checked linkage to tranny, checked cv shafts, and the fluid looks great and does not smell burnt. Where the linkage goes to the tranny there is some electrical thing I was wondering if that has something to do with it because the tranny has never acted funny or did it right before.

thank you very much

micheal