P1137moderate severityPowertrain
HO2S Lean System Bank 1 Sensor 2
on 2020 Buick Encore 1.4L Turbo I4 · AWD
What this code means
The bank 1 downstream oxygen sensor indicates a lean condition. This can affect catalyst monitoring and fuel control.
Symptoms
- Check engine light on
- Poor fuel economy
- Possible catalyst code
Common causes
- Exhaust leak near sensor
- Faulty downstream O2 sensor
- Wiring or connector fault
- Lean fuel condition
Diagnostic steps
- Scan and view downstream O2 data
- Inspect exhaust for leaks
- Check sensor wiring and connector
- Replace O2 sensor if faulty
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0006
Fuel Shutoff Valve A Control Circuit Low
P0007
Fuel Shutoff Valve A Control Circuit High
P0008
Engine Position System Performance - Bank 1
P0009
Engine Position System Performance - Bank 2
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1