Why would my 2000 buick lasabre just stop when i was driving?

I have a 2000 buick lasabre that was running beautifully. The car is in excellent condition, and has always been taken care of so well. While driving it today down the road, the motor just quick. The lights and everything stayed on... It starts up, but once i stop pushing the gas petal, it dies again. No dummy lights came on... there is gas in the tank, the battery is fine... Any ideas? (it doesnt run rough)Why would my 2000 buick lasabre just stop when i was driving?if it was the fuel pump the car wouldnt start, would it? it is fuel injected...Why would my 2000 buick lasabre just stop when i was driving?Sounds like the fuel pump ....