2021 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

DTC P2004: TGV Control Stuck Open Bank 1: Notes

1. -

DTC detecting condition: 

Immediately at fault recognition

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .
  1. CHECK DTC  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor or a general scan tool, read the DTC of [Engine].

      Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC other than P2004 displayed? (Current malfunction)

    Yes  : Check the appropriate DTC using the "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DIAGNOSTIC TROUBLE CODE (DTC) .

    No  : Go to  2 .

  2. CHECK TUMBLE GENERATOR VALVE RH  .
    1. Remove the intake manifold assembly.

      Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>INTAKE MANIFOLD ASSEMBLY>REMOVAL .

    2. Check the tumble generator valve.

    Is there any dirt or clogging with foreign objects in the tumble generator valve?

    Yes  : Clean the tumble generator valve.

    No  : Replace the tumble generator valve RH. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>TUMBLE GENERATOR VALVE .

    NOTE: The tumble generator valve cannot be disassembled.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.