From the sounds of it , I'm going to go with the fuel pump. I've had on go out and it did the same thing. If you floor it will sputtered and sometimes run smooth. Last option is the fuel filter. You could have water in tour fuel and it could be causing the issue. One last thing it could be is you pissed someone off and they put a marble or two in your gas tank. It runs fine until it's sucked up by the fuel line...then when the car is towed away it will start fine. Don't ask why I know this, cause I've never done this to anyone...ever.
