Troubleshooting Flowchart - Oxygen Sensor (D 15137, D16Z6 engine)

Self-diagnosis Check Engine light indicates code 1: A problem in the Oxygen (0z) Sensor circuit.
The Oxygen sensor detects the oxygen content in the exhaust gas and signals the ECU. In operation, the ECU receives the signals from the sensor and varies the duration during which fuel is injected. The oxygen sensor has an internal heater. The heater stabilizes the sensor's output. The oxygen sensor is installed in the exhaust manifold.