88 Taurus just---dies
Our '88 Taurus 3.0 has started an annoying and dangerous habit of dying (engine just stops for no apparent reason), sometimes when coming to a stop, sometimes when minding our own business driving up the road.
It happens sporadically, sometimes 3-4 times in an hour, and she starts back up again as if nothing happened. Car was very recently tuned up professionally, idle adjusted, etc.
Mechanic says (rightfully) that it's difficult to diagnose because of the intermittent nature. My gut is saying fuel pump, but if that doesn't work, it would be an awfully expensive experiment.
Suggestions to diagnose this problem?