the "wrench light" comes on and the car shuts down while I'm driving.

There is a known ETB (electronic throttle body)uto defect with some Ford's that would certainly cause the engine to cut out or shut down. The "wrench" light is known to appear on the instrument cluster when this failure occurs. Driving a car that has an unresolved pattern of shutting itself off while underway is extremely dangerous. Find a shop you can trust (check for the Repair Pal Certified shops in your area) and let them get to the bottom of this before you have an accident. Good luck.