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Home >> Subaru >> 1998 >> Forester Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Diagnostic Tests >> DTC P0133 (FO2_R): Front O2S Circuit Slow Response
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DTC P0133 (FO2_R): Front O2S Circuit Slow Response

  1. If DTC P0133 is only code set, check exhaust system for any leaks and repair as necessary. If exhaust system is okay, replace front O2S. If other codes are set, go to next step.
  2. If DTC P0130 exists, diagnose DTC P0130 first. Clear DTC and retest system.