Fuel Injection problems of the 2003 Jeep Grand Cherokee

Over a one (1) month period, my car has been serviced by the dealer four (4) times due to a hesitation when accelerating especially at speeds over 60 mph. When attempting to accelerate the car begins to stutter and the malfunction indicator light appears and continually flashes. This problem has nearly caused me to be in two accidents! when this first began, the problem occurred only at higher speeds. However, by the third and fourth occurrence it was happening at only 20 mph and when at a stop light the car would shake and begin to die. There are only 12,000 miles on the vehicle and it is less than one (1) year old.