2001 Sunfire

I have a 2001 sunfire. It has failed to start for me and I had to have it towed twice this past couple of weeks. I have had it to two seperate technicians which turned out the same result. When the car is brought in it seems as though there is no power going to the fuel pump. After checking the connections and the wiring for corrosion and no apparent problems found the car just starts right back up again and works fine both the techs have told me that they have stopped and started it numerous times trying to get it to mimic the same problem but it won't. I don't know what could be wrong that it just looses power to the fuel pump sometimes. It ran for a week between episodes.