I was thinking fuel system...Could also be an injector for Fuel pressure regulator. If it's your fuel pump, turn your key to the start position, you should hear the pump, if you hear it, then it should be find, but if you know someone with a fuel pressure tester there's a cap on your fuel rail that you can check your fuel pressure this will also tell you if your FPR is sticking. If you havn't replaced your filter in about 5,000 miles, then it's best to replace it if it's bad or not...injectors...check to see if your leaking from your vents on the side of the injector (4 vents per injector) you can also pull them to see what the little rubber cups look like on the tip of the injector, if they are messed up, maybe it's your spray pattern?