2006 Mazda 6 MazdaspeedFACTORY OEM SERVICE PROCEDURE

DTC P2187: Notes

DTC P2187 DETECTION CONDITION AND POSSIBLE CAUSES

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

Diagnostic support note 
  • This is a continuous monitor. (Fuel system)
  • MIL illuminates if the PCM detects the above malfunctioning 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 conditions during the first drive cycle.
  • FREEZE FRAME DATA is available.
  • DTCs are stored in the PCM memory.
POSSIBLE CAUSE 
  • Misfire
  • Front HO2S deterioration
  • Front HO2S heater malfunction
  • MAF sensor malfunction
  • Pressure regulator malfunction
  • Fuel pressure sensor malfunction
  • Relief valve (built-in fuel delivery pipe) malfunction
  • Spill valve control solenoid valve (built-in high pressure fuel pump) malfunction
  • High pressure fuel pump malfunction
  • Fuel pump malfunction
  • Fuel filter clogged or restricted
  • Fuel leakage on fuel line from fuel delivery pipe and fuel pump
  • Exhaust system leakage
  • Purge solenoid valve malfunction
  • Purge solenoid hoses improper connection
  • Air suction in intake-air system
  • Insufficient engine compression
  • Variable valve timing control system improper operation
  • PCM malfunction
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.