Oxygen Sensor
- Warm engine to normal operating temperature and allow it to idle. Disconnect oxygen sensor wiring harness connector. Attach voltmeter between oxygen sensor and ground. Increase engine to 4000 RPM until voltmeter indicates about .55 volts (.7 volts on 323).
- Increase and decrease engine speed quickly several times. When speed is increased, voltmeter reading should be between .5-1.0 volts. When engine speed is decreased, reading should be between 0-.4 volts. If readings are incorrect, replace oxygen sensor.