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2009 SUBARU LEGACY

2.5L H4AWDCVTgas
13 active safety recalls on this vehicle — view recalls
Repairs0Labor504Torque3865Fluid9DTC861Battery0Maintenance0Recalls13
P0150moderate severityPowertrain

O2 Sensor Circuit Bank 2 Sensor 1

on 2009 Subaru Legacy 2.5L H4 · AWD

What this code means

General malfunction in the upstream O2 sensor circuit for Bank 2.

Symptoms

  • Check Engine Light
  • Poor fuel economy
  • Rough idle
  • Failed emissions

Common causes

  • Faulty O2 sensor
  • Exhaust leak
  • Wiring damage

Diagnostic steps

  1. Test sensor voltage
  2. Check for exhaust leaks
  3. Inspect wiring

Repair notes

Replace O2 sensor.

Other Powertrain codes on this vehicle

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