How to Replace Oxygen Sensors for a 1999 Jeep Cherokee
- 1). Open the hood of your Jeep. Disconnect the negative battery cable. The terminal will be marked with the letters NEG or show a (-) symbol.
- 2). Raise the front of your Jeep Cherokee with a jack and support it on jack stands.
- 3). Disconnect the faulty sensor's electrical plug. You may need to use a small flat-head screwdriver to disconnect the plug from the adapter.
- 4). Unbolt the oxygen sensor with a crescent wrench. Use a oxygen sensor socket to remove the sensor if it is difficult to reach.
- 5). Apply a small amount of anti-seize compound to the threads of the new sensor.
- 6). Connect the new sensor's electrical plug to the adapter. Firmly bolt the sensor in place using your wrench.
- 7). Raise the Jeep above the jack stands. Remove the stands and lower the vehicle to the ground. Reconnect the negative battery cable.
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