Subaru Fault Code

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P0028

Loss of High-RPM Power / Misfires

System

Engine / VVT

Symptom

Loss of High-RPM Power / Misfires

Diagnosis & fix steps

LOGIC: Intake Valve Control Solenoid Circuit Range/Performance (Bank 2). ACTION: Swap the Bank 2 variable valve lift pressure switch with Bank 1. If the fault moves, replace the switch. If it stays, clean the cylinder head oil mesh screen behind the AVCS supply banjo bolt.

Red Seal field insights

Banjo Bolt Screen: A miniature mesh filter hidden inside the cylinder head AVCS oil supply banjo bolt clogs with degraded oil, starving the phaser and pressure switch of line pressure.

Same code keeps coming back?

That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.

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Read before you touch anything

  • This is general reference information, not a repair manual. It is for trained, qualified technicians.
  • Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
  • Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
  • You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
  • Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.

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