HO2S Circuit Low Variance Lean Indication
2007-2016 Volvo S80 3.2L I6
Description
The ECM detected that the upstream O2 sensor is showing a persistent lean-biased signal with insufficient switching activity. The sensor is stuck or sluggish on the lean side.
Symptoms
- Check Engine Light
- Poor fuel economy
- Rough idle
- Failed emissions test
Common Causes
- Aging O2 sensor with degraded response
- Exhaust leak before O2 sensor
- Vacuum leak causing actual lean condition
- Contaminated O2 sensor
- Wiring issue affecting sensor output
Diagnostic Steps
- Monitor O2 sensor signal switching with scan tool
- Check for exhaust leaks
- Perform smoke test for vacuum leaks
- Inspect O2 sensor for contamination
- Test sensor wiring
Repair Notes
Replace the upstream O2 sensor if switching response has degraded.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1131 on Other Vehicles
Common Questions
What does code P1131 mean on a 2007-2016 Volvo S80?
P1131 stands for "HO2S Circuit Low Variance Lean Indication". The ECM detected that the upstream O2 sensor is showing a persistent lean-biased signal with insufficient switching activity. The sensor is stuck or sluggish on the lean side.
What are the symptoms of P1131 on a Volvo S80?
Common symptoms of P1131 include: Check Engine Light, Poor fuel economy, Rough idle, Failed emissions test.
What causes P1131 on a 2007-2016 Volvo S80?
Common causes of P1131 include: Aging O2 sensor with degraded response, Exhaust leak before O2 sensor, Vacuum leak causing actual lean condition, Contaminated O2 sensor, Wiring issue affecting sensor output.