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Home >> Nissan-Datsun >> 2008 >> Quest Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P1211 Through P2A03 >> DTC P1421 Cold Start Control >> On Board Diagnosis Logic
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On Board Diagnosis Logic

DTC DETECTING CONDITION AND POSSIBLE CAUSE

DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421
Cold start emission reduction strategy monitoring ECM does not control ignition timing and engine idle speed properly when engine is started with pre-warming up condition.
  • Lack of intake air volume
  • Fuel injection system
  • ECM