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2015 SUBARU LEGACY
3.6L H6•AWD•CVT•gas
3 active safety recalls on this vehicle — view recalls
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Repairs0Labor482Torque1444Fluid9DTC1872Battery1Maintenance0Recalls3
P0176low severityPowertrain

Fuel Composition Sensor Circuit

on 2015 Subaru Legacy 3.6L H6 · AWD

What this code means

Malfunction in the fuel composition sensor circuit, used in flex-fuel vehicles to detect ethanol content.

Symptoms

  • Check Engine Light
  • Poor driveability on E85
  • Incorrect fueling for fuel type

Common causes

  • Faulty fuel composition sensor
  • Wiring damage
  • Sensor contamination

Diagnostic steps

  1. Test sensor output
  2. Inspect wiring
  3. Check for contamination

Repair notes

Replace fuel composition sensor.

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