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2015-2019 SUBARU LEGACY

2.5L H4AWDCVTgas
14 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque4912Fluid9DTC919Battery0Maintenance0Recalls14
P0046moderate severityPowertrain

Turbo/Supercharger Boost Control Solenoid Circuit Range/Performance

on 2015-2019 Subaru Legacy 2.5L H4 · AWD

What this code means

The boost control solenoid is not responding within expected parameters.

Symptoms

  • Check Engine Light
  • Overboosting or underboosting
  • Reduced power
  • Surging

Common causes

  • Sticking solenoid
  • Vacuum leak
  • Wastegate stuck
  • Boost pressure sensor fault

Diagnostic steps

  1. Monitor boost pressure vs commanded
  2. Test solenoid operation
  3. Check vacuum lines
  4. Inspect wastegate

Repair notes

Replace solenoid or repair wastegate.

Other Powertrain codes on this vehicle

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