Oxygen (O2) Sensor
- Disconnect O2 sensor from wire harness connector. Start engine, and bring to normal operating temperature. Backprobe sensor connector, and measure voltage between O2 sensor and ground.
- While observing voltage, open throttle fully, and then release suddenly. Voltage should be greater than 0.6 volt at wide open throttle and less than 0.4 volt when throttle is quickly released. If voltage readings are not as specified, check wiring to sensor. If wiring is okay, replace O2 sensor.