The engine doesn't seem to be getting any gas.

The low fuel indicator light came on today with somewhere between 1/8 to 1/4 of tank of gas left. I filled the tank but the indicator light did not go out nor did the gauge move from to the Full position - in fact, it dropped all the way down to Empty. I drove the car approximately 80 miles when it began to "cut out" - it was as if the car was not getting any gas. I just had the fuel pump replaced a few weeks ago so I don't think that is the problem unless it is a bad part. Is it possible the situation w/the fuel indicator light was indicative of something much more serious w/the fuel delivery system? I would like to know a few theories before having a mechanic look at the car.