1992 Subaru Loyale fuel pump

Is there a fuel pump malfunction if when I take off from stop signs and lights there is a hesitation, followed by a loud hum and a sound that sounds like there is air, instead of gas surging thru the intake since when I am depressing the gas pedal, there is no acceleration? Then, around 20 -25, it beginsto surge again, noise followed by a surge of acceleration. Highway driving, while Imaintain areg. Speed is OK. But, when I drive on local rodas w/ many stops and gos-- the problems arise. Slow acceleration, surges of small acceleration after I have applied the brakes. What does this mean please?