Possible causes
– Faulty Heated Oxygen Sensor Bank 1 or 2
– Heated Oxygen Sensor Bank 1 or 2 harness is open or shorted
– Heated Oxygen Sensor Bank 1 or 2 circuit poor electrical connection
– Heated Oxygen Sensor Bank 1 or 2 harness is open or shorted
– Heated Oxygen Sensor Bank 1 or 2 circuit poor electrical connection
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P1031 SATURN Description
Heated Oxygen Sensor (HO2S)