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DTC P2177 [L3 Turbo]

id0102b7812300

DTC P2177 | Fuel system too lean at off idle
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DETECTION CONDITION | • PCM monitors the short term fuel trim (SHRTFT) and 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 the preprogrammed criteria, the PCM determines that the 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 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 • A/F sensor deterioration • A/F sensor 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 • Exhaust system leakage • 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

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED • Has FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
No | Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available? | Yes | Perform repair or diagnosis according to the available Service information. If the vehicle is not repaired, go to the next step.
No | Go to the next step.
3 | VERIFY RELATED PENDING CODE OR STORED DTCS • Turn the ignition switch to off, then to the ON position (Engine off). • Verify related pending code or stored DTCs. • Are other DTCs present? | Yes | If misfire the DTC is present, go to Step 8. If other DTCs is present, go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No | If driveability concern is present, go to Step 8. If not, go to the next step.
4 | IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA • Is DTC P2177 on FREEZE FRAME DATA? | Yes | Go to the next step.
No | Go to troubleshooting procedures for DTC on FREEZE FRAME DATA.
5 | VERIFY CURRENT INPUT SIGNAL STATUS (IGNITION SWITCH TO THE ON POSITION/IDLE) • Access the APP1, APP2, ECT, MAF, TP and VSS PIDs using the WDS or equivalent. • Is there any signal that is far out of specification when the ignition switch is at the ON position and the engine runs? | Yes | Inspect the sensor and excessive resistance in related wiring harnesses. Repair if necessary. Then go to Step 20.
No | Go to the next step.
6 | VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION • Inspect the same PIDs as Step 5 while simulating FREEZE FRAME DATA condition. • Is there any signal which causes drastic changes? | Yes | Inspect the sensor and related wiring harnesses repair or replace it. Then go to Step 20.
No | Go to the next step.
7 | VERIFY CURRENT INPUT SIGNAL STATUS OF A/F SENSOR • Access the O2S11 for P2177 PID using the WDS or equivalent. • Check the PID under following accelerator pedal condition in NEUTRAL. • Is the PID reading normal? - -0.1-0.1 A when idle - More than 0.25 mA just after release of accelerator pedal (lean condition). | Yes | Go to the next step.
No | Visually inspect for any gas leakage between the exhaust manifold and the A/F sensor. Then go to Step 20.
8 | VERIFY CURRENT INPUT SIGNAL STATUS OF MAF SENSOR • Connect the WDS or equivalent to the DLC-2. • Start the engine. • Access the MAF PID. • Verify that the MAF PID changes quickly according to engine speed. • Is the PID normal? | Yes | Go to the next step.
No | Replace the MAF/IAT sensor, then go to Step 20.
9 | INSPECT FOR EXCESSIVE AIR SUCTION OF INTAKE AIR SYSTEM • Visually inspect for loosen, cracks or damages hoses on intake-air system. • Is there any malfunction? | Yes | Repair or replace the source of air suction, then go to Step 20.
No | Go to the next step.
10 | INSPECT PURGE SOLENOID OPERATION • Perform the Purge Control System Inspection. (See Purge Control System Inspection.) • Does the purge control system work properly? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to inspection result, then go to Step 20.
11 | INSPECT FUEL PRESSURE (HIGH-SIDE) • Access and monitor FUEL_PRES PID. • Is the FUEL_PRES PID value within the specified? (See Using the WDS or Equivalent.) | Yes | Go to Step 15.
No | Go to the next step.
12 | IDENTIFY CAUSE BY FUEL PRESSURE SENSOR OR HIGH PRESSURE FUEL PUMP • Is the vehicle accelerate performance normally? | Yes | Go to the next step.
No | Go to Step 14.
13 | INSPECT FUEL PRESSURE SENSOR • Inspect the fuel pressure sensor. • Is fuel leakage found? (SeeFUEL PRESSURE SENSOR INSPECTION [L3 Turbo].) • Is the fuel pressure sensor normal? | Yes | Go to Step 15.
No | Replace the fuel delivery pipe, then go to Step 20.
14 | INSPECT HIGH PRESSURE FUEL PUMP • Replace the high pressure fuel pump • Monitor FUEL_PRES PID • Is the FUEL_PRES PID value within the specified? (See Using the WDS or Equivalent.) | Yes | Go to Step 20.
No | Go to the next step.
15 | INSPECT FUEL PRESSURE (LOW-SIDE) • Connect the fuel pressure gauge between fuel pump and high pressure fuel pump. • Measure the low side fuel pressure. (See FUEL LINE PRESSURE INSPECTION [L3 Turbo].) • Is the low side fuel pressure within the specified? | Yes | Go to the next step.
No | Inspect for following: • Fuel line restriction • Fuel filter clogging If okay replace the fuel pump. Then go to Step 20.
16 | INSPECT IGNITION SYSTEM • Perform the spark test. (See Spark Test.) • Is strong blue spark visible at each cylinder? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to spark test result, then go to Step 20.
17 | INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [L3 Turbo].) • Is it normal? | Yes | Go to the next step.
No | Implement the engine overhaul for repairs, then go to Step 20.
18 | INSPECT VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION • Inspect the variable valve timing control system operation. (See Variable Valve Timing Control System Operation Inspection.) • Does the variable valve timing control system work properly? | Yes | Go to the next step.
No | Repair or replace the malfunctioning part according to inspection results, then go to Step 20.
19 | INSPECT FUEL INJECTOR OPERATION • Remove the fuel injector. • Inspect the fuel injector (resistance, injection amount). (See FUEL INJECTOR INSPECTION [L3 Turbo].) • Is the fuel injector normal? | Yes | Go to the next step.
No | Replace the fuel injector, then go to the next step.
20 | VERIFY TROUBLESHOOTING OF DTC P2177 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear the DTC from the PCM memory using the WDS or equivalent. • Perform the PCM Adaptive Memory Produce Drive Mode. (See OBD DRIVE MODE [L3 Turbo].) • Is the PENDING CODE for this DTC present? | Yes | Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [L3 Turbo].)
No | Go to the next step.
21 | VERIFY AFTER REPAIR PROCEDURE • Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [L3 Turbo].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No | Troubleshooting completed.