How to Replace the Oxygen Sensor on a Pontiac Montana
- 1). Allow the Montana's engine to cool for 10 minutes. The engine will still be warm to the touch, however this is necessary since the oxygen sensor is easiest to replace while the engine is warm.
- 2). Locate the exhaust manifold; the oxygen sensor is positioned on top of the manifold. Refer to your Montana owner's manual if needed.
- 3). Using a socket wrench and an oxygen sensor socket, loosen the oxygen sensor. Use a 22 mm socket if you do not have access to an oxygen sensor socket. Continue to loosen the oxygen sensor until the you can easily remove the sensor by lifting it off the manifold.
- 4). Insert the new oxygen sensor into the connector and push in to ensure the sensor plugs into place. Close the hood of the Montana.
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