Exhaust Gas Oxygen (O2) Sensor
- O2 sensor is mounted in exhaust pipe, below exhaust manifold. Measure voltage between pigtail connector and ground. A Scan tester may be used to measure voltage when in closed loop.
- Ensure engine is at normal operating temperature. Operate engine for 40 seconds (minimum) and measure voltage. Voltage should be 0.1-1.0 volt. If voltage is not within specification, replace sensor.