What could cause my 2001 escort to idle and run rough only when gas is below half a tank?

If your 2001 Escort idles and runs rough when the gas tank is below half, it could be due to a clogged fuel filter or a failing fuel pump that struggles to maintain pressure when the fuel level is low. Additionally, sediment or debris in the tank may be getting picked up as the fuel level drops, affecting fuel flow. It's also possible that the fuel gauge is inaccurate, leading to inadequate fuel supply. Checking the fuel system components would be a good next step.