In each position of the selector lever, try starting the engine with the parking brake on. With the lever in Park and Neutral, it should start and in all other positions the engine should remain off. When the engine fires at positions besides Park and Neutral, adjust the linkage and try again. Turn the key if the engine starts in areas other than Park or Neutral. The switch needs replacement. First, disconnect the negative battery cable. Then put the selector lever in the Low position with the parking brake engaged. Before continuing, lift your car, put it on jackstands, and remove the power connector from the Neutral Safety Switch. Separate the switch and O-ring from the car, put new ones in their place, secure the switch to recommended force, and watch out not to damage or tear the switch walls. Do these three steps: Connect the electrical plug, reconnect the negative battery wire, and check that the engine runs best when the gear selector is either in Neutral or Park.