P1086low severityPowertrain
Tumble Generator Valve 2 LH Position Sensor Low
on 1997 Subaru Impreza 2.2L H4 · AWD
What this code means
The PCM has detected a low-voltage condition on the Tumble Generator Valve 2 left-hand position sensor circuit. The TGV system creates tumble motion in the intake air to improve combustion efficiency and reduce emissions at low loads.
Symptoms
- Check Engine Light
- Minor reduction in fuel economy
- Slightly higher emissions
Common causes
- Faulty TGV position sensor
- Wiring short to ground in sensor circuit
- Corroded TGV sensor connector
- Damaged sensor due to heat exposure
Diagnostic steps
- Check TGV 2 LH position sensor voltage on scan tool
- Inspect sensor connector for corrosion
- Test sensor wiring for shorts to ground
- Check 5V reference at sensor
- Compare readings between left and right TGV sensors
Repair notes
Replace the TGV position sensor or repair the wiring if shorted to ground.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1