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DTC P2177: Notes

DTC P2177 [L3] CHART

DTC P2177

Fuel system too lean at off idle

DETECTION CONDITION

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

Diagnostic support note

This is a continuous monitor (Fuel system).
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
Front HO2S deterioration
Front HO2S heater 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 improper operation
Purge solenoid valve malfunction (stuck open)
Purge solenoid hoses improper connection
Air suction in intake air system
Insufficient engine compression
Variable valve timing control system improper operation
PCM malfunction