Doesn't want to Move when the accelerator is being pressed

My 1993 Accord periodically acts as if it doesn't want to move when the accelerator is being pressed. I assume that the car's computer is sending some sort of warning, because when this problem happens the "D" or drive gear indicator on the dashboard flashes. I thought maybe the transmission was low on fluid, but when I checked the level all is well. What could possibly be going wrong with the car?