This is just a hotstart problem due to the high under bonnet temps. What happens is the fuel rail gets hot and the injection system has to get rid of the fuel vapour in the rail. It does this by holding the injectors open longer to let the vapour out of the system. There is no return to the tank in the Ford system which means that unless the car is using more than idle fuel amounts there is not enough fuel flow to keep the injector rail cool.