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2015 SUBARU LEGACY

3.6L H6AWDCVTgas
3 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque3898Fluid9DTC907Battery0Maintenance0Recalls3
P1090moderate severityPowertrain

Tumble Generator Valve 1 RH Stuck Open

on 2015 Subaru Legacy 3.6L H6 · AWD

What this code means

The PCM has detected that the Tumble Generator Valve 1 on the right-hand cylinder bank is stuck in the open position. The valve should close at low engine loads to create intake air tumble.

Symptoms

  • Check Engine Light
  • Reduced combustion efficiency at low loads
  • Slightly rough idle
  • Higher emissions

Common causes

  • Carbon buildup preventing valve closure
  • Faulty TGV actuator motor
  • Broken TGV linkage
  • TGV shaft binding
  • Actuator wiring issue

Diagnostic steps

  1. Command TGV closed with scan tool and monitor position sensor
  2. Inspect TGV valve for carbon buildup or physical obstruction
  3. Check TGV actuator motor operation
  4. Inspect linkage for damage
  5. Test actuator wiring

Repair notes

Clean carbon from the TGV valve; replace the TGV actuator if the motor or linkage has failed.

Other Powertrain codes on this vehicle

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