Repair 7

How to Replace the Oxygen Sensor in a 1999 Pontiac Grand Am

For many years, the federal government has mandated that automobile manufacturers include emission control systems on their vehicles. One of the various components in the emission control system is the oxygen sensor (O2 sensor). This sensor measures the amount of oxygen present in the exhaust; the vehicles computer uses that information to adjust the fuel/air mixture for peak efficiency. Oxygen sensors require periodic replacement. On the 1999 Pontiac Grand AM, replacing the O2 sensor is something vehicle owners can do themselves.

Instructions

1

Park the vehicle, set the parking brake and open the engine hood.

2

Locate the oxygen sensor. It is mounted in the exhaust manifold towards the back of the engine above the exhaust pipe flange.

3

Remove the wire from the sensor. Using the appropriate socket, back out the sensor by rotating it counterclockwise. It is not unusual for it to be very tight, requiring firm pressure to the socket wrench. Spraying an anti-seize fluid at the top of the threads can help loosen the sensor for easier removal.

4

Install the new sensor into the hole and tighten firmly -- 30 foot-pounds of torque is recommended.

5

Attach the new wire to the sensor and the job is complete.