See Figures 1 and 2
The oxygen sensor is located in the exhaust manifold and provides input to the ECU relating oxygen content of the exhaust gas. The ECU uses this information to vary air/fuel ratio. A lean air/fuel mixture causes a greater oxygen content and a rich air/fuel mixture causes less oxygen content. On 1987-90 2.5L engines, the oxygen sensor is equipped with an electrically heated element that keeps the sensor at operating temperature under all conditions.
REMOVAL & INSTALLATION
See Figures 3 and 4
- Raise the vehicle and support it safely. Allow the exhaust system to cool sufficiently in order to permit servicing without burning yourself.
- Disengage the wire connector from the oxygen sensor.
- Remove the oxygen sensor from the exhaust manifold.
- If not already done, coat the threads of the replacement sensor with anti-seize compound. Be careful not to contaminate the oxygen sensor probe with the anti-seize.
- Install the oxygen sensor into the exhaust manifold and tighten to 22-35 ft. lbs. (30-47 Nm) Engage the wire connector.