Car studders when fuel gets below half a tank

[4d_guy]

I have a 95 mark viii with 77k miles on it. Whenever the fuel level goes below half a tank, the car studders when I start accelerating (even when I do it nicely). Above a half a tank, the car runs fine. Also, when I'm on the highway, the car runs fine regardless of how full the tank is. By studder, I mean the rpms drop off to about 200, surge to about 1500, then level out. I know the fuel gauge is reading properly, and the engine itself is in top shape. Does anyone have any ideas? Thanks

 

[Abbens]

did you check the fuel pressure when the gas is below half a tank?

 

[kustomizingkid]

Change the fuel filter and then check the pressure, and check it under load.