Recently Iv had a real funny situation. Car ran great untill it tried to go into boost. Once it hit atmospheric pressure (0) the fuel pressure would go all over the place. We tried everything but, in the end the fuel line from fuel filter to rail was getting a pocket inside and would restrict the fuel.
If you feal it is a fuel issue I would get a gauge on it so you know what the fuel pressure is and then trouble shoot the car. It could be a bunch of things like plug wires rotor etc etc.