I had a very similar problem, it ended up being the fuel pump even though it was only two years old. Went to start it and fired right up went down to the local 7-11 turned it off got my coffee then when to turn it on and it would fire up then die right out. Got it back to my house, check the fuel pump relay and pump. Relay was good pump was no good. I kicked the gas tank a few times through the driver's side wheel well and then turned the key and it fired right up. Went out and listened to the pump and it wasnt making that continous hummmmm, it was more like hummm, bump, bump, humm. Turned it off then on again and pump ran fine. I repalced the pump and never had a problem since.