What do you do if a few days after replacing the starter the engine wouldn't turn off and your replaced ignition switch and solenoid but it is still doing it?

be sure to double and triple check the wiring of the starter. If for some reason the two posts coming off the starter are grounded the flow of electricity will keep moving keeping the motor running. the positive battery cable should go stright to the starter to the positive post(usually the one on the top when you look down at it from top of motor), then the ground should actually be somewhere on the transmission(usually the post on the bottom looking down) then there is usually a third connection point(no post) that goes to the solenoid, if not go through the solenoid then to the starter with the positive wire. good luck