Turbo/Supercharger Wastegate Actuator Stuck Open
2012-2012 Subaru Legacy 3.6L H6
The 2012 Subaru Legacy is equipped with a 3.6L flat-6 engine. Below you'll find detailed p3004 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
The wastegate actuator is stuck in the open position, preventing the turbo from building proper boost pressure.
Symptoms
- Check Engine Light
- No boost pressure
- Significant loss of power
- Engine feels naturally aspirated
- Poor acceleration at all speeds
Common Causes
- Wastegate actuator rod seized
- Actuator diaphragm ruptured
- Wastegate valve carbon buildup
- Vacuum line disconnected
- Actuator linkage broken
Diagnostic Steps
- Check wastegate actuator vacuum line
- Manually operate wastegate actuator rod
- Inspect actuator diaphragm for leaks
- Check for carbon deposits on wastegate valve
- Verify boost pressure with gauge
Repair Notes
Replace wastegate actuator. Clean carbon from wastegate valve and housing. Check turbo shaft play.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P3004 on Other Vehicles
Common Questions
What does code P3004 mean on a 2012-2012 Subaru Legacy?
P3004 stands for "Turbo/Supercharger Wastegate Actuator Stuck Open". The wastegate actuator is stuck in the open position, preventing the turbo from building proper boost pressure.
What are the symptoms of P3004 on a Subaru Legacy?
Common symptoms of P3004 include: Check Engine Light, No boost pressure, Significant loss of power, Engine feels naturally aspirated, Poor acceleration at all speeds.
What causes P3004 on a 2012-2012 Subaru Legacy?
Common causes of P3004 include: Wastegate actuator rod seized, Actuator diaphragm ruptured, Wastegate valve carbon buildup, Vacuum line disconnected, Actuator linkage broken.
Last updated: March 2026