Fuel Delivery problems of the 2004 Subaru Impreza

2004 Impreza sti - repeated momentary fuel cut out during left turns. Never during right turns; left turns only. Low speed and high speed. At all fuel levels. Will happen 3 times in one day, then go away for 3 weeks before occuring again. Occurs frequently during left turns and u-turns at intersections. Car hesitates for a moment as if fuel to engine was momentarily cut. Engine does not stall however and comes back to normal operation after the momentary hesitation. Have tried to resolve issue with both my local authorized Subaru dealer and corporate Subaru of America service rep. Neither were able to recreate problem and say they are unable to resolve issue. Continued fuel cut out for no apparent reason causing car to hesitate is a serious safety issue. I am afraid to make left turns at intersections in front of oncoming traffic for fear that my car will not respond. My car has no modifications and has been experiencing this problem since it had less than 12,000 miles. Several other owners of identical car also reporting exact same issues. I will have them join me in this complaint process to NHTSA.