Oxygen Sensor: Testing and Inspection

Dwell Terminal:

OXYGEN SENSOR TESTING

1. Thoroughly warm up engine. Engine must be operating in closed loop. This test will not be valid if oxygen sensor is too cool.
2. Connect dwell or duty cycle meter to dwell terminal. Use 4 cylinder scale.
3. With engine idling, disconnect oxygen sensor and ground ECM end of terminal.
4. If the meter reading is under 10~ after 30 seconds, the indication is bad oxygen sensor connections or a faulty oxygen sensor.
5. If the meter reading is over 10~ after 30 seconds, refer to COMPUTERIZED ENGINE CONTROLS.
6. Clear codes after completing work.