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HOMESERVICE MANUALSMAZDA20086 S SPORT, 4D HATCHBACK, STANDARDREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISON-BOARD DIAGNOSTIC [ENGINE CONTROL SYSTEM (AJ]DTC P0021 [AJ]NOTES
2008 Mazda 6 s Sport, 4D Hatchback, Standard

DTC P0021 [AJ]: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
DTC P0021 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0021 CMP timing over-advanced (LH)
DETECTION CONDITION 
  • The actual valve timing is over-advanced by 20°  from the target valve timing when the OCV is controlled in the maximum valve timing retard condition.

    MONITORING CONDITIONS 

    • Engine coolant temperature is above 63 °C {145 °F} 

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTC is stored in PCM memory.
POSSIBLE CAUSE 
  • Oil control valve malfunction
  • Spool valve in OCV (LH) is stuck in advance position.
  • Variable valve timing actuator (LH) is stuck in advance position.
  • Loose timing chain or improper valve timing
  • PCM malfunction
RENDER: 1.0x

NO RELATED

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