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Home >> Mazda >> 2006 >> MPV ES >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System (AJ)] >> DTC P2187, P2189 >> Notes
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DTC P2187, P2189: Notes

DTC P2187, P2189 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES

DTC P2187 Fuel system too lean at idle (Right bank)
DTC P2189 Fuel system too lean at idle (Left bank)
DETECTION CONDITION 
  • PCM monitors short term fuel trim (SHRTFT) long term fuel trim (LONGFT) during closed loop fuel control at idle. If the LONGFT and the sum total of these fuel trims exceed preprogrammed criteria. PCM determines that fuel system is too lean at idle.

Diagnostic support note 

  • This is a continuous monitor. (FUEL SYSTEM)
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA is available
  • DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Misfire
  • HO2S (RF, LF) deterioration
  • HO2S heater (RF, LF) malfunction
  • MAF sensor malfunction
  • Pressure regulator (built-in fuel injection pump) malfunction
  • Fuel pump malfunction
  • Fuel filter clogged or restricted
  • Fuel leakage on fuel line from fuel delivery pipe and fuel pump
  • Leakage exhaust system
  • Purge solenoid valve malfunction
  • Purge solenoid hoses improper connection
  • Air suction in intake-air system
  • Insufficient engine compression
  • PCM malfunction