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Home >> Volvo >> 1990 >> 760 GLE, AW71L >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Fuel Control >> Oxygen (O2) Sensor
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Oxygen (O2) Sensor

  1. Warm engine to normal operating temperature. Connect exhaust gas analyzer. Disconnect O2 sensor wire (at O2 sensor) from ECU.
  2. Connect a jumper wire between ECU wiring (O2 sensor harness side) and ground. CO content should increase, indicating ECU and its connections are okay.
  3. Connect a voltmeter to O2 sensor. While engine is running voltmeter should fluctuate at approximately 0.5 volts if CO constant is normal. Replace O2 sensor if not within specification.
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