Back to 2004 Subaru Legacy

2004 SUBARU LEGACY

3.0L H6AWDCVTgas
11 active safety recalls on this vehicle — view recalls
Repairs0Labor591Torque3666Fluid9DTC730Battery0Maintenance0Recalls11
P1088low severityPowertrain

Tumble Generator Valve 1 RH Position Sensor Low

on 2004 Subaru Legacy 3.0L H6 · AWD

What this code means

The PCM has detected a low-voltage condition on the Tumble Generator Valve 1 right-hand position sensor circuit. This is the right bank counterpart to P1086.

Symptoms

  • Check Engine Light
  • Minor fuel economy reduction
  • Slightly increased emissions

Common causes

  • Faulty TGV 1 RH position sensor
  • Wiring short to ground
  • Corroded connector
  • Sensor damage from heat

Diagnostic steps

  1. Check TGV 1 RH position sensor voltage on scan tool
  2. Inspect sensor connector
  3. Test wiring for shorts to ground
  4. Verify reference voltage
  5. Compare left and right bank TGV readings

Repair notes

Replace the TGV position sensor if faulty; repair wiring if shorted.

Other Powertrain codes on this vehicle

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