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DTC P2178, P2180 [AJ]

BME010202100W04

DTC P2178 DTC P2180 | Fuel system too rich at off idle (Right bank) Fuel system too rich at off idle (Left bank)
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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 rich at off-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
• EGR valve improper operation
• IMCC improper operation
• Purge solenoid valve improper operation
• Purge solenoid valve malfunction (stuck open)
• Purge solenoid hoses improper connection
• PCV valve malfunction
• PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED • Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (Fuel system related) been recorded? | Yes | Go to the next step.
No | Record the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Information and/or on-line repair information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to the available repair 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 ON (Engine off). • Verify related pending code or stored DTCs using the WDS or equivalent. • Is other DTC present? | Yes | If misfire DTC is present, go to Step 8. If other DTC is present, go to appropriate DTC troubleshooting procedure. (See DTC TABLE [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed)).)
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 P2178 or P2180 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 ON/IDLE) • Access ECT, MAF, TP and VSS PIDs using the WDS or equivalent. • Is there any signal that is far out of specification when ignition switch is ON and engine runs? | Yes | Inspect suspected sensor and excessive resistance in related wiring harnesses. Repair if necessary. Then go to Step 15.
No | Go to the next step.
6 | VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION • Inspect same PIDs as Step 5 while simulating FREEZE FRAME DATA condition. • Is there any signal which causes drastic changes? | Yes | Inspect suspected sensor and related wiring harnesses repair or replace it. Then go to Step 15.
No | Go to the next step.
7 | VERIFY CURRENT INPUT SIGNAL STATUS OF FRONT HO2S • Start the engine and warm it up completely. • Access O2S11 (with P2178) or O2S21 (with P2180) PID using the WDS or equivalent. • Check PID under following accelerator pedal condition (in PARK).
• Is PID reading normal?

- More than 0.45 V when accelerator pedal is suddenly depressed (rich condition).

- Less than 0.45 V just after release of accelerator pedal (lean condition)

Yes
Go to the next step.
No | Visually inspect for any gas leakage between exhaust manifold and front HO2S. • If there is no leakage, replace front HO2S. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [AJ].) Then go to Step 15.
8 | VERIFY CURRENT INPUT SIGNAL STATUS OF MAF SENSOR • Start the engine. • Access the MAF PID using the WDS or equivalent. • Verify that the MAF PID changes quickly according to engine speed. • Is the PID normal? | Yes | Go to the next step.
No | Replace MAF/IAT sensor, then go to Step 15.
9 | INSPECT PURGE SOLENOID OPERATION • Carry out Purge Control System Inspection. (See Purge Control System Inspection.) • Does purge control system work properly? | Yes | Go to the next step.
No | Repair or replace malfunctioning part according to inspection result, then go to Step 15.
10 | INSPECT PCV VALVE OPERATION • Inspect PCV valve operation. (See PCV VALVE INSPECTION [AJ].) • Is PCV valve normal? | Yes | Go to the next step.
No | Replace PCV valve, then go to Step 15.
11 | INSPECT EGR VALVE OPERATION • Carry out EGR Control System Inspection. (See EGR Control System Inspection.) • Does EGR control system work properly? | Yes | Go to the next step.
No | Repair or replace malfunctioning part according to inspection result, then go to Step 15.
12 | INSPECT IMCC OPERATION • Carry out Intake Manifold Communication Control (IMCC) Operation Inspection. (See Intake Manifold Communication Control (IMCC) System Inspection.) • Does IMCC work properly? | Yes | Go to the next step.
No | Repair or replace malfunctioning part according to inspection result, then go to Step 15.
13 | INSPECT FUEL LINE PRESSURE • Perform the "FUEL LINE PRESSURE INSPECTION". (See FUEL LINE PRESSURE INSPECTION [AJ].) • Is there any malfunction? | Yes | If fuel pressure is too high, replace fuel pump nit, then go to Step 15. If fuel line pressure is low, go to the next step.
No | Go to the next step.
14 | INSPECT FUEL LEAKAGE FROM FUEL PUMP TO FUEL DELIVERY PIPE • Visually inspect fuel line for any leakage. • Is any fuel leakage found? | Yes | Replace suspected fuel line, then go to the next step.
No | Inspect for foreign materials or stain inside fuel filter (low-pressure). If for foreign materials or stain inside fuel filter (low-pressure), clean of fuel tank and filter. Then go to the next step.
15 | VERIFY TROUBLESHOOTING OF DTC P2178 AND P2180 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear DTC from PCM memory using WDS or equivalent. • Perform the PCM Adaptive Memory Produce Drive MODE. (See OBD DRIVE MODE [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed)).)
• Is the PENDING CODE same DTC present?
Yes
Replace PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [AJ].)
No | Go to the next step.
16 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [AJ].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection. (See DTC TABLE [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed)).)
No | Troubleshooting completed.