SFI SYSTEM, Diagnostic DTC:P0171, P0172, P0174, P0175, P1170, P117B

DTC Code DTC Name
P0171 System Too Lean (Bank 1)
P0172 System Too Rich (Bank 1)
P0174 System Too Lean (Bank 2)
P0175 System Too Rich (Bank 2)
P1170 Port Injector Fuel Performance
P117B Direct Injector Fuel Performance

DESCRIPTION

The fuel trim is related to the feedback compensation value, not to the basic injection time. The fuel trim consists of both the short-term and the long-term fuel trim.

The short-term fuel trim is fuel compensation that is used to constantly maintain the air fuel ratio at stoichiometric levels. The signal from the air fuel ratio sensor indicates whether the air fuel ratio is rich or lean compared to the stoichiometric ratio. This triggers a reduction in the fuel injection volume if the air fuel ratio is rich and an increase in the fuel injection volume if it is lean.

Factors such as individual engine differences, wear over time and changes in operating environment cause short-term fuel trim to vary from the ideal theoretical value. The long-term fuel trim controls overall fuel compensation. The long-term fuel trim compensates for long term deviations of the fuel trim from the ideal theoretical value. These long term deviations result from the corrections made by the short-term fuel trim.

If both the short-term fuel and long-term fuel trim are lean or rich beyond predetermined values, it is interpreted as a malfunction, the ECM illuminates the MIL and sets a DTC.

DTC No. DTC Detection Condition Trouble Area

P0171

P0174

With warm engine and stable air fuel ratio feedback, fuel trim considerably in error to lean side

(2 trip detection logic)

  • Intake system

  • Fuel injector assembly for port injection

  • Fuel injector assembly for direct injection

  • Mass air flow meter

  • Engine coolant temperature sensor

  • Fuel pressure

  • Gas leaks from exhaust system

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • PCV valve and hose

  • PCV hose connections

  • ECM

  • Wire harness or connector

P0172

P0175

With warm engine and stable air fuel ratio feedback, fuel trim considerably in error to rich side

(2 trip detection logic)

  • Mass air flow meter

  • Engine coolant temperature sensor

  • Fuel injector assembly for port injection

  • Fuel injector assembly for direct injection

  • Ignition system

  • Fuel pressure

  • Gas leaks from exhaust system

  • Open or short in air fuel ratio sensor (bank 1, 2 sensor 1) circuit

  • Air fuel ratio sensor (bank 1, 2 sensor 1)

  • ECM

  • Wire harness or connector
P1170 Although a DTC is stored for a rich or lean condition, the amount of fuel trim during direct injection is normal (2 trip detection logic)

  • Fuel injector assembly for port injection

  • Fuel injector assembly for direct injection

  • Fuel pressure

  • ECM
P117B Although a DTC is stored for a rich or lean condition, the amount of fuel trim during port injection is normal (2 trip detection logic)

Tech Tips


  • When DTC P0171 or P0174 is set, the actual air-fuel ratio is on the lean side. When DTC P0172 or P0175 is set, the actual air-fuel ratio is on the rich side.

  • If the vehicle runs out of fuel, the air-fuel ratio is lean and DTC P0171 or P0174 may be set. The MIL is then illuminated.

  • When DTC P1170 or P117B is output, it may not be possible to precisely determine whether the port injection or the direct injection is malfunctioning, depending on the conditions. In this case, perform an Active Test (control the injection way) to determine which injection system is malfunctioning.

MONITOR DESCRIPTION

Under closed loop fuel control, fuel injection volumes that deviate from those estimated by the ECM cause changes in the long-term fuel trim compensation value. The long-term fuel trim is adjusted when there are persistent deviations in the short-term fuel trim values. Deviations from the ECM's estimated fuel injection volumes also affect the average fuel trim learning value, which is a combination of the average short-term fuel trim (fuel feedback compensation value) and the average long-term fuel trim (learning value of the air fuel ratio). If the average fuel trim learning value exceeds the malfunction threshold, the ECM interprets this as a malfunction in the fuel system and sets a DTC.


A01FGQFE40

MONITOR STRATEGY

Required Sensors/Components Air fuel ratio sensor, Mass air flow meter, Crankshaft position sensor
Frequency of Operation Continuous

TYPICAL ENABLING CONDITIONS

Fuel system status Closed loop
Battery voltage 11 V or more
Either of the following conditions 1 or 2 is met: -
1. Engine speed Less than 1100 rpm
2. Engine load 10% or more

TYPICAL MALFUNCTION THRESHOLDS

P0171, P0172, P0174 and P0175: Fuel-Trim Lean/Rich
EVAP purge-cut Executing
Either of the following conditions 1 or 2 is met: -
1. Average between short-term fuel trim and long-term fuel trim 35% or more (varies with engine coolant temperature)
2. Average between short-term fuel trim and long-term fuel trim -35% or less (varies with engine coolant temperature)
P1170: Fuel Trim (Port Injection)
DTCs of fuel system have already been set -
EVAP purge-cut Executing
Injection mode Port
Both of the following conditions 1 and 2 are met: -
1. Average between short-term fuel trim and long-term fuel trim Less than 35% (varies with engine coolant temperature)
2. Average between short-term fuel trim and long-term fuel trim More than -35% (varies with engine coolant temperature)
P117B: Fuel Trim (Direct Injection)
DTCs of fuel system have already been set -
EVAP purge-cut Executing
Injection mode Direct
Both of the following conditions 1 and 2 are met: -
1. Average between short-term fuel trim and long-term fuel trim Less than 35% (varies with engine coolant temperature)
2. Average between short-term fuel trim and long-term fuel trim More than -35% (varies with engine coolant temperature)

CONFIRMATION DRIVING PATTERN

A01FEKME06

  1. Connect the GTS to the DLC3.

  2. Turn the engine switch on (IG) and turn the GTS on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Click here.

  4. Turn the engine switch off.

    Tech Tips


    • Let the engine cool down.

    • Touch a radiator hose to check that the engine coolant temperature has dropped.

  5. Turn the engine switch on (IG) and turn the GTS on [A].

  6. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or more) with all the accessories switched off [B].

  7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.

  8. Read the Pending DTCs [C].

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  9. Drive the vehicle at between 60 and 120 km/h (37 and 75 mph) and at an engine speed of between 1400 rpm and 3200 rpm for 5 minutes or more [D].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

  10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.

  11. Read the pending DTCs [E].

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, the system is normal.

WIRING DIAGRAM

Refer to DTC P2195 Click here.

INSPECTION PROCEDURE

Tech Tips

Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F Sensor function provided in the Active Test. The Control the Injection Volume for A/F Sensor function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume for A/F Sensor operation using the GTS


  1. Connect the GTS to the DLC3.

  2. Start the engine.

  3. Turn the GTS on.

  4. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.

  5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / Ptrol AF Control / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.

  6. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).

  7. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the GTS

Tech Tips


  • Change the fuel injection volume within the range of -12.5% to +12.5%.

  • Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

GTS Display (Sensor) Injection Volume Status Voltage

AFS Voltage B1S1

AFS Voltage B2S1

(Air fuel ratio)

 +12.5% Rich Below 3.1 V
-12.5% Lean Higher than 3.4 V

O2S B1S2

O2S B2S2

(Heated oxygen)

 +12.5% Rich Higher than 0.55 V
-12.5% Lean Below 0.4 V

Note

The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

Case Air Fuel Ratio Sensor (Sensor 1) Output Voltage Heated Oxygen Sensor (Sensor 2) Output Voltage Main Suspected Trouble Area
1 A01FEJUE08 A01FIL1E08 A01FEJUE08 A01FFTIE06 -
2 A01FEJUE08 A01FHKDE01 A01FEJUE08 A01FFTIE06

  • Air fuel ratio sensor

  • Air fuel ratio sensor heater

  • Air fuel ratio sensor circuit
3 A01FEJUE08 A01FIL1E08 A01FEJUE08 A01FHKDE01

  • Heated oxygen sensor

  • Heated oxygen sensor heater

  • Heated oxygen sensor circuit
4 A01FEJUE08 A01FHKDE01 A01FEJUE08 A01FHKDE01

  • Fuel injector assembly

  • Fuel pressure

  • Gas leak from exhaust system (Air fuel ratio extremely rich or lean)

Tech Tips


  • Bank 1 refers to the bank that includes the No. 1 cylinder*.

    *: The No. 1 cylinder is the cylinder which is farthest from transmission.

  • Bank 2 refers to the bank that does not include the No. 1 cylinder.

  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor farthest away from the engine assembly.

  • Read freeze frame data using the GTS The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was moving or stationary, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

  • A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.

  • A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0171, P0172, P0174, P0175, P1170 AND/OR P117B)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Read the DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 or P117B A
      P0171, P0172, P0174, P0175, P1170 and/or P117B and other DTCs B

      Tech Tips

      If any DTCs other than P0171, P0172, P0174, P0175, P1170 or P117B are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. PERFORM SYSTEM CHECK (CONTROL THE INJECTION WAY)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Port.

    6. Read the value Short #1 and Long FT #1 and/or Short FT #2 and Long FT #2.

      OK
      Short FT #1 (#2) + Long FT #1 (#2) = Between -19% and +19%

    7. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Direct.

    8. Read the value Short FT #1 and Long FT #1 and/or Short FT #2 and Long FT #2.

      OK
      Short FT #1 (#2) + Long FT #1 (#2) = Between -19% and +19%
      Result
      Item Proceed to
      Port Direct
      OK OK A
      OK NG B
      NG OK C
      NG NG D

    B

    CHECK FUEL PRESSURE SENSOR Click here

    C

    CHECK FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION) Click here

    D

    CHECK PCV HOSE CONNECTIONS Click here

    A

  3. CHECK IF VEHICLE HAS RUN OUT OF FUEL IN PAST


    1. Has the vehicle run out of fuel in the past?


    NO

    CHECK FOR INTERMITTENT PROBLEMS Click here

    YES

    DTC CAUSED BY RUNNING OUT OF FUEL

  4. CHECK PCV HOSE CONNECTIONS


    1. Check the PCV hose (w/ canister pump module) connections Click here.

    2. Check the PCV hose (w/o canister pump module) connections Click here.

      OK
      PCV valve and hose are connected correctly and are not damaged.

    NG

    REPAIR OR REPLACE PCV HOSE

    OK

  5. CHECK INTAKE SYSTEM


    1. Check the intake system for vacuum leaks Click here.

      OK
      No leaks in intake system.

      Tech Tips

      Perform "Inspection After Repair" after replacing the intake system Click here.


    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  6. PERFORM ACTIVE TEST USING GTS (CONTROL THE INJECTION VOLUME FOR A/F SENSOR)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn GTS on.

    4. Warm up the engine and run the engine at an engine speed of 2500 rpm for approximately 90 seconds.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.

    6. Perform the Control the Injection Volume for A/F Sensor operation with the engine in an idling.

    7. Monitor the output voltages of the A/F and HO2 sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the GTS

      Tech Tips


      • Change the fuel injection volume within the range of -12.5% to 12.5%.

      • The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

      • If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

      GTS Display (Sensor) Injection Volume Status Voltage

      AFS Voltage B1S1 or AFS Voltage B2S1

      (A/F)

      		 12.5% Rich Less than 3.1 V
      -12.5% Lean More than 3.4 V

      O2S B1S2 or O2S B2S2

      (HO2)

      		 12.5% Rich More than 0.55 V
      -12.5% Lean Less than 0.4 V
      Result

      Status

      AFS Voltage B1S1

      or

      AFS Voltage B2S1

      Status

      O2S B1S2

      or

      O2S B2S2

      A/F Condition and

      A/F Sensor Condition

      		 Suspected Trouble Area Proceed to
      Lean/Rich Lean/Rich Normal - A
      Lean Lean Actual air-fuel ratio lean

      • Ventilation valve and hose

      • Ventilation hose connections

      • Injector for port injection

      • Gas leakage from exhaust system

      • Air induction system

      • Fuel pressure

      • Mass Air Flow (MAF) meter

      • Engine Coolant Temperature (ECT) sensor

      		 A
      Rich Rich Actual air-fuel ratio rich

      • Gas leakage from exhaust system

      • Ignition system

      • Fuel pressure

      • MAF meter

      • ECT sensor

      		 A
      Lean Lean/Rich A/F sensor malfunction

      • A/F sensor

      		 B
      Rich Lean/Rich A/F sensor malfunction

      • A/F sensor

      		 B

      Lean: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor output voltage (AFS Voltage) is consistently higher than 3.4 V, and the heated oxygen sensor output voltage (O2S) is consistently below 0.4 V.

      Rich: During the Control the Injection Volume for A/F Sensor Active Test, the AFS Voltage is consistently below 3.1 V, and the O2S is consistently higher than 0.55 V.

      Lean/Rich: During the Control the Injection Volume for A/F Sensor Active Test, the output voltage of the heated oxygen sensor alternates correctly.

      Tech Tips

      Refer to "Data List / Active Test" [AFS Voltage B1S1, AFS Voltage B2S1, O2S B1S2 and O2S B2S2] Click here.


    B

    Click here

    A

  7. READ VALUE USING GTS (COOLANT TEMP)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.

    5. Read the Coolant Temp twice, when the engine is both cold and warmed up.

      Standard
      With cold engine
      Same as ambient air temperature.
      With warm engine
      Between 75 and 100°C (167 and 212°F)

      Tech Tips

      Perform "Inspection After Repair" after replacing the engine coolant temperature sensor Click here.


    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here

    OK

  8. READ VALUE USING GTS (MAF)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF, Coolant Temp and Engine Speed.

    6. Allow the engine to idle until Coolant Temp reaches 75°C (167°F) or higher.

    7. Read MAF with the engine speed at 3000 rpm.

      Standard
      Between 12.7 gm/sec and 13.7 gm/sec (shift lever: N, A/C: Off).

    NG

    CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION) Click here

    OK

  9. CHECK FOR EXHAUST GAS LEAK


    1. Check for exhaust gas leaks.

      OK
      No gas leaks.

      Tech Tips

      Perform "Inspection After Repair" after replacing the exhaust system Click here.


    OK

    PERFORM CONFIRMATION DRIVING PATTERN Click here

    NG

    REPAIR OR REPLACE EXHAUST SYSTEM

  10. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)


    1. Inspect the air fuel ratio sensor Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.


    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  11. CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM)


    1. Disconnect the air fuel ratio sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      F62-1 (HA1A) - F4-5 (HA1A) Always Below 1 Ω
      F62-3 (A1A+) - F3-23 (A1A+) Always Below 1 Ω
      F62-4 (A1A-) - F3-22 (A1A-) Always Below 1 Ω
      F46-1 (HA2A) - F4-6 (HA2A) Always Below 1 Ω
      F46-3 (A2A+) - F3-21 (A2A+) Always Below 1 Ω
      F46-4 (A2A-) - F3-20 (A2A-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F62-1 (HA1A) or F4-5 (HA1A) - Body ground Always 10 kΩ or higher
      F62-3 (A1A+) or F3-23 (A1A+) - Body ground Always 10 kΩ or higher
      F62-4 (A1A-) or F3-22 (A1A-) - Body ground Always 10 kΩ or higher
      F46-1 (HA2A) or F4-6 (HA2A) - Body ground Always 10 kΩ or higher
      F46-3 (A2A+) or F3-21 (A2A+) - Body ground Always 10 kΩ or higher
      F46-4 (A2A-) or F3-20 (A2A-) - Body ground Always 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the air fuel ratio sensor connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  12. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor Click here.


    NEXT

  13. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the engine switch off and wait for at least 30 seconds.

    5. Turn the engine switch on (IG) and turn the GTS on.

    6. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.


    NEXT

  14. CHECK WHETHER DTC OUTPUT RECURS (DTC P0171, P0172, P0174, P0175, P1170 AND/OR P117B)


    1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    2. Read the pending DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 and/or P117B A
      DTC is not output B

    B

    END

    A

  15. CHECK FUEL PRESSURE (LOW PRESSURE)


    1. Check the fuel pressure Click here.

      Result
      Result Proceed to
      NG A
      OK B

    B

    CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION) Click here

    A

  16. CHECK FUEL PUMP OPERATION (LOW PRESSURE)


    1. Check the fuel pump operation Click here.


    NG

    REPLACE FUEL PUMP (LOW PRESSURE) Click here

    OK

  17. CHECK FUEL LEAK (LOW PRESSURE SIDE)


    1. Check for fuel leaks (low pressure side).

      OK
      No leaks.

    NG

    REPAIR OR REPLACE FUEL SYSTEM (LOW PRESSURE SIDE)

    OK

    CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL LINE AND FILTER

  18. CHECK FUEL PRESSURE SENSOR


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    6. While revving the engine, check that the fuel pressure fluctuates.

      Standard
      Idling
      3500 to 4500 kPa (35.7 to 45.9 kgf/cm2, 508 to 653 psi).
      2500 rpm (Depress accelerator pedal fully)
      7000 to 9000 kPa (71.4 to 91.8 kgf/cm2, 1015 to 1305 psi)

      Tech Tips

      The A/C switch and all accessory switches should be off, and the shift lever should be in the N or P position, and the engine should be fully warmed up.


    NG

    CHECK MISFIRE COUNT Click here

    OK

  19. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Direct.

      Tech Tips

      The A/C switch and all accessory switches should be off, and the shift lever should be in the N or P position, and the engine should be fully warmed up.

    5. Read the value Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4).

      Result
      Item Proceed to
      Fuel Pump Duty (D4) Short FT #1 + Long FT #1 Short FT #2 + Long FT #2
      10% to 40% - - A
      40% or more -20% or less -20% or less B
      10% or less +20% or more +20% or more B
      40% or more +20% or more +20% or more C
      10% or less -20% or less -20% or less D

    B

    REPLACE FUEL PRESSURE SENSOR Click here

    C

    CHECK FUEL RELIEF VALVE Click here

    D

    REPLACE ECM Click here

    A

  20. READ VALUE USING GTS


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Direct.

      Tech Tips

      The A/C switch and all accessory switches should be off, and the shift lever should be in the N or P position, and the engine should be fully warmed up.

    5. Read the value Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4).

      Result
      Item Proceed to
      Fuel Pump Duty (D4) Short FT #1 + Long FT #1 Short FT #2 + Long FT #2
      10% to 40% -25% or less -25% or less A
      10% to 40% -25% or less -25% to +25% B
      10% to 40% -25% to +25% -25% or less C
      10% to 40% +30% or more +30% or more A
      10% to 40% +25% or more -25% to +25% B
      10% to 40% -25% to +25% +25% or more C
      10% to 40% -25% to +25% -25% to +25% D

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly (for direct injection) Click here.


    B

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION (BANK 1)) Click here

    C

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION (BANK 2)) Click here

    D

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION (ALL CYLINDERS)) Click here

  21. CHECK MISFIRE COUNT


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Active test / Control the Injection Way / Direct.

    6. Allow the engine to idle.

    7. Monitor all of the misfire count values that are displayed on the GTS: Powertrain / Engine and ECT / Data List / Cylinder #1 Misfire Count to Cylinder #6 Misfire Count.

      If no misfire counts occur for any of the cylinders, perform the following procedure:


      1. Move the shift lever to D.

      2. Monitor all of the misfire rate values that are displayed on the GTS

        Result
        Misfire Count Proceed to
        No misfire counts, or misfire counts occur randomly in all cylinders A
        Misfire counts occur in particular cylinder B

        Tech Tips

        Perform "Inspection After Repair" after replacing the fuel injector assembly (for direct injection) Click here.


    B

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) Click here

    A

  22. INSPECT INJECTOR DRIVER


    1. Replace the injector driver with known good ones from another vehicle.

      Note

      Do not disconnect and reconnect the connectors with the engine switch on (IG), as the injector driver (EDU) may be damaged.

    2. Connect the GTS to the DLC3.

    3. Turn the engine switch on (IG).

    4. Turn the GTS on.

    5. Clear the DTCs Click here.

    6. Turn the engine switch off and wait for at least 30 seconds.

    7. Turn the engine switch on (IG) and turn the GTS on.

    8. Start the engine and warm it up.

    9. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    11. Read the pending DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 and/or P117B A
      DTC is not output B

    B

    END (INJECTOR DRIVER IS DEFECTIVE)

    A

  23. CHECK FUEL RELIEF VALVE


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Start the engine.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    6. Record the Fuel Press value.

    7. Turn the engine switch off.

    8. Wait for 10 seconds.

    9. Turn the engine switch on (IG) and turn the GTS on.

    10. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

    11. Compare the Fuel Press value recorded with the engine running to the Fuel Press value currently shown on the GTS

      Result
      Inspection Result Proceed to
      Fuel Press value is maintained A
      Fuel Press value drops B

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump assembly (for high pressure) Click here.


    B

    REPLACE FUEL RELIEF VALVE Click here

    A

    REPLACE FUEL PUMP FOR HIGH PRESSURE Click here

  24. CHECK FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION)


    1. Check the injection volume (whether fuel volume is high or low, and whether injection pattern is poor).

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly (for port injection) Click here.


    NG

    REPLACE FUEL INJECTOR FOR PORT INJECTION Click here

    OK

    REPLACE ECM Click here

  25. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER CONNECTOR CONNECTION)


    1. Check the connection and terminal contact pressure of connectors and wire harness between the mass air flow meter sub-assembly and ECM Click here.

      Tech Tips

      Repair any problems.


    NEXT

  26. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the engine switch off and wait for at least 30 seconds.

    5. Turn the engine switch on (IG) and turn the GTS on.

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.


    NEXT

  27. CHECK WHETHER DTC OUTPUT RECURS (DTC P0171, P0172, P0174, P0175, P1170 AND/OR P117B)


    1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    2. Read the pending DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 and/or P117B A
      DTC is not output B

    B

    END

    A

  28. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)


    1. Disconnect the MAF meter connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)
      Tester Connection Condition Specified Condition
      F39-5 (VG) - F1-25 (VG) Always Below 1 Ω
      F39-4 (E2G) - F1-24 (E2G) Always Below 1 Ω
      Standard Resistance (Check for short)
      Tester Connection Condition Specified Condition
      F39-5 (VG) or F1-25 (VG) - Body ground Always 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the MAF meter connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  29. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY


    1. Replace the mass air flow meter sub-assembly Click here.

      Tech Tips


      • If the result of the inspection performed in step 8 indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly.

      • Perform "Inspection After Repair" after replacing the mass air flow meter Click here.


    NEXT

  30. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG) and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the engine switch off and wait for at least 30 seconds.

    5. Turn the engine switch on (IG) and turn the GTS on.

    6. Start the engine and warm it up.

    7. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.


    NEXT

  31. CHECK WHETHER DTC OUTPUT RECURS (DTC P0171, P0172, P0174, P0175, P1170 AND/OR P117B)


    1. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    2. Read the pending DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 and/or P117B A
      DTC is not output B

    NG

    END

    OK

    REPLACE ECM Click here