I have a 95 jeep grand cherokee has the 4.0 engine it it does have to crank a little bit longer than it should, idles fine but when driving jerks real bad and real hard, has died a time or two and when it did the gas padel fell to the floor but started back fine and the gas pedal returned to normal, the check engine light just flickers on and off it did read a misfire in cylinder one once, and the causes the headlights to flicker slightley as well but the jerking is so bad you cant really drive it i have changed the spark plugs have no clue what to do please help

If "gas pedal fell to floor" it has to be something wrong with cruise control?

Check the fuel pressure. How long has it been since the fuel filter, distributor cap , rotor, and wires were replaced?