Possible causes – Faulty Front Oxygen Bank 1 Sensor– Front Oxygen Sensor Bank 1 harness is open or shorted– Front Oxygen Sensor Bank 1 circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light)
Possible causes – Faulty Front Oxygen Sensor– Front Oxygen Sensor harness is open or shorted– Front Oxygen Sensor circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light)
Possible causes – Faulty Glow Plug Control Module– Glow Plug Control Module harness is open or shorted– Glow Plug Control Module circuit poor electrical connection When is the code detected? The Engine Control Module (ECM) has detected a concern in
Possible causes – Faulty HO2S21– HO2S21 harness is open or shorted– HO2S21 circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 VOLKSWAGEN Description HO2S21 Heather Oxygen Sensor Bank 2 Sensor 1
Possible causes – Faulty HO2S21– HO2S21 harness is open or shorted– HO2S21 circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 AUDI Description HO2S21 Heather Oxygen Sensor Bank 2 Sensor 1
Possible causes – Faulty Oxygen Sensor– Oxygen Sensor harness is open or shorted– Oxygen Sensor circuit poor electrical connection Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 BMW Description O2 sensor circuit dynamic test bank 2
Possible causes – Faulty Oxygen Sensor– Vacuum leak affecting bank 1 only– Fuel injector problem bank 1– Check for cylinder misfire on bank 1– Engine mechanical condition Tech notes Though the Oxygen (O2) sensor, the Engine Control Module (ECM) has
Possible causes – Faulty Swirl control valve control solenoid valve– Swirl control valve control solenoid valve circuit is open or shorted– Swirl control valve circuit is open or shorted– Faulty swirl control valve– Faulty Swirl control valve actuator When is
Possible causes – Faulty Swirl control valve control solenoid valve– Swirl control valve control solenoid valve circuit is open or shorted– Swirl control valve circuit is open or shorted– Faulty swirl control valve– Faulty Swirl control valve actuator When is
Possible causes – Vacuum leak affecting bank 1 only– Fuel injector problem bank 1– Check for cylinder misfire on bank 1– Engine mechanical condition– Faulty O2 sensor. Tech notes Though the Oxygen (O2) sensor, the Engine Control Module (ECM) has
Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 CHEVROLET Description A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when
Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 CADILLAC Description A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when
Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 BUICK Description A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when
Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 GMC Description A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when
Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 Description Lack Of HO2S Switch – Sensor Indicates Lean is one of the definitions for the P1131; however your vehicle’s manufacturer may have a different definition for the
Symptoms – Engine Light ON (or Service Engine Soon Warning Light)