pontiacfriend

HEy all i am new to the forum. I have a tech question My G6 died yesterday. looks like the Fuel gauge is not reading right and the car ran out of gas. Added gas and the car seems to be running fine other then the gauge reads wrong. The mech i took it to says i need a new pump($550) put the car runs???? So I was thinking the Fuel Level Sensor??? I seen a lot of stuff on the web about the sending unit but some say it hasn't fixed their problem!! any ideas.