how old is the fuel filter?
the car might have enough pumped into the rail and the line after the filter to pull you through first and then when you hit 2nd and lay on it it starts to starve for fuel..... letting up on the gas would cure this.... and the 4 seconds that you describe would allow the partialy clogged filter to refill the rail agian....
Could be a number of things. . . .this was just the first thought that came to mind....
the car might have enough pumped into the rail and the line after the filter to pull you through first and then when you hit 2nd and lay on it it starts to starve for fuel..... letting up on the gas would cure this.... and the 4 seconds that you describe would allow the partialy clogged filter to refill the rail agian....
Could be a number of things. . . .this was just the first thought that came to mind....