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 trims are lean or rich beyond predetermined values, it is interpreted as a malfunction, and the ECM illuminates the MIL and sets a DTC.

DTC No. DTC Detection Condition Trouble Area

P0171

P0174

With stable air-fuel ratio feedback, fuel trim considerably in error to lean side

(2 trip detection logic)

  • Intake system

  • Injector for port injection

  • Injector for direct injection

  • Mass air flow meter sub-assembly

  • 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)

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

  • Air fuel ratio sensor heater circuits

  • PCV valve and hose

  • PCV hose connections

  • ECM

  • Wire harness or connector

P0172

P0175

With stable air-fuel ratio feedback, fuel trim considerably in error to rich side

(2 trip detection logic)

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Injector for port injection

  • Injector 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)

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

  • Air fuel ratio sensor heater circuits

  • ECM

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

  • Injector for port injection

  • Injector for direct injection

  • Fuel pressure

  • ECM
P117B Although a DTC is stored for rich or lean condition, the amount of fuel trim during port injection is normal

  • Injector for port injection

  • Injector for direct injection

  • Fuel pressure

  • ECM

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 the total of the short-term and long-term fuel trim values is within the malfunction threshold (and the engine coolant temperature is more than 75°C [167°F]), the system is functioning normally.

  • 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 fault in the fuel system and sets a DTC.


A0162SSE45

CONFIRMATION DRIVING PATTERN

A01602DE04

  1. Connect the intelligent tester to the DLC3.

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

  3. Clear the DTCs Click here.

  4. Turn the engine switch off.

    Tech Tips


    • Let the engine cool down.

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

  5. Turn the engine switch on (IG) and turn the tester 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 / DTC / Pending.

  8. Read the pending DTC [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 km/h and 120 km/h (37 mph 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 / DTC / Pending.

  11. Read the pending DTC [E].

    Tech Tips


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

    • If no pending DTC is 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 (A/F) sensor, Heated Oxygen (HO2) 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 intelligent tester.


  1. Connect the tester to the DLC3.

  2. Start the engine and turn the tester on.

  3. Warm up the engine at an engine speed of 2000 rpm for approximately 90 seconds.

  4. On the tester, enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor.

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

  6. 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 tester.

Tech Tips


  • The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.

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

Tester Display (Sensor) Injection Volume Status Voltage

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 +25% Rich Less than 3.1 V

AFS Voltage B1S1 or AFS Voltage B2S1

(Air fuel ratio)

 -12.5% Lean More than 3.4 V

O2S B1S2 or O2S B2S2

(Heated oxygen)

 +25% Rich More than 0.55 V

O2S B1S2 or O2S B2S2

(Heated oxygen)

 -12.5% Lean Less than 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 A0162ADE01 A0160FEE04 A0162ADE01 A0161P9E01 -
2 A0162ADE01 A015ZP2E01 A0162ADE01 A0161P9E01

  • Air fuel ratio sensor

  • Air fuel ratio sensor heater

  • Air fuel ratio sensor circuit
3 A0162ADE01 A0160FEE04 A0162ADE01 A015ZP2E01

  • Heated oxygen sensor

  • Heated oxygen sensor heater

  • Heated oxygen sensor circuit
4 A0162ADE01 A015ZP2E01 A0162ADE01 A015ZP2E01

  • Injector

  • Fuel pressure

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

Tech Tips


  • Read freeze frame data using the intelligent tester. 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 running or stopped, 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.

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

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

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

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

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

PROCEDURE


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


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine / DTC.

    4. Read DTCs.

      Result
      Result Proceed to
      P0171, P0172, P0174, P0175, P1170 or P117B A
      P0171, P0172, P0174, P0175, P1170 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. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Port.

    4. Read the value.


      1. Enter the following menus: Data List / All Data / 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%

    5. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.

    6. Read the value.


      1. Enter the following menus: Data List / All Data / 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 FOR PORT INJECTION Click here

    D

    CHECK PCV HOSE Click here

    A

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


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


    YES

    DTC CAUSED BY RUNNING OUT OF FUEL

    NO

    CHECK FOR INTERMITTENT PROBLEMS Click here

  4. CHECK PCV HOSE

    OK
    PCV hose is connected correctly and is not damaged.

    NG

    REPAIR OR REPLACE PCV HOSE

    OK

  5. CHECK INTAKE SYSTEM


    1. Check the intake system for vacuum leakage.

      OK
      No leakage from intake system.

    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  6. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Warm up the engine at an engine speed of 2000 rpm for approximately 90 seconds.

    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / Data List / AFS Voltage B1S1, AFS Voltage B2S1, O2S B1S2 and O2S B2S2.

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

    6. 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 tester.

      Tech Tips


      • The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.

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

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

      Tester Display (Sensor) Injection Volume Status Voltage

      AFS Voltage B1S1 or AFS Voltage B2S1

      (Air fuel ratio)

      		 +25% Rich Less than 3.1 V

      AFS Voltage B1S1 or AFS Voltage B2S1

      (Air fuel ratio)

      		 -12.5% Lean More than 3.4 V

      O2S B1S2 or O2S B2S2

      (Heated oxygen)

      		 +25% Rich More than 0.55 V

      O2S B1S2 or O2S B2S2

      (Heated oxygen)

      		 -12.5% Lean Less than 0.4 V
      Result

      Status

      AFS Voltage B1S1

      or

      AFS Voltage B2S1

      Status

      O2S B1S2

      or

      O2S B2S2

      Air Fuel Ratio Condition and

      Air Fuel Ratio Sensor Condition

      		 Misfire Suspected Trouble Area Proceed to
      Lean Lean Actual air-fuel ratio lean May occur

      • PCV valve and hose

      • PCV hose connections

      • Injector for port injection

      • Injector for direct injection

      • Gas leaks from exhaust system

      • Intake system

      • Fuel pressure

      • Mass air flow meter

      • Engine coolant temperature sensor

      		 A
      Rich Rich Actual air-fuel ratio rich -

      • Injector for port injection

      • Injector for direct injection

      • Gas leaks from exhaust system

      • Ignition system

      • Fuel pressure

      • Mass air flow meter

      • Engine coolant temperature sensor

      		 A
      Lean Lean/Rich Air fuel ratio sensor malfunction -

      • Air fuel ratio sensor

      		 B
      Rich Lean/Rich Air fuel ratio sensor malfunction -

      • Air fuel ratio sensor

      		 B

      • Lean:


        • During Control the Injection Volume for A/F Sensor, the air fuel ratio sensor output voltage (AFS) is consistently more than 3.4 V, and the heated oxygen sensor output voltage (O2S) is consistently less than 0.4 V.


      • Rich:


        • During Control the Injection Volume for A/F Sensor, the AFS is consistently less than 3.1 V, and the O2S is consistently more than 0.55 V.


    B

    INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE) Click here

    A

  7. READ VALUE USING INTELLIGENT TESTER (COOLANT TEMP)


    1. Connect the intelligent tester to the DLC3.

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

    3. Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.

    4. Read the Data List 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 95°C (167 and 203°F)

    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here

    OK

  8. READ VALUE USING INTELLIGENT TESTER (MAF)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

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

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

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

      Standard
      Between 17 g/sec. and 23 g/sec. (shift lever: N; A/C: Off).

    NG

    CHECK HARNESS AND CONNECTOR Click here

    OK

  9. CHECK FOR EXHAUST GAS LEAK


    1. Check for exhaust gas leaks.

      OK
      No gas leaks.

    OK

    PERFORM CONFIRMATION DRIVING PATTERN Click here

    NG

    REPAIR OR REPLACE EXHAUST SYSTEM

  10. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)


    1. A015ZERE16

      Disconnect the air fuel ratio sensor connector.

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

      Standard Resistance (Bank 1 Sensor 1)
      Tester Connection Condition Specified Condition
      1 (HA1A) - 2 (+B) 20°C (68°F) 1.8 to 3.4 Ω
      1 (HA1A) - 4 (A1A-) Always 10 kΩ or higher
      Standard Resistance (Bank 2 Sensor 1)
      Tester Connection Condition Specified Condition
      1 (HA2A) - 2 (+B) 20°C (68°F) 1.8 to 3.4 Ω
      1 (HA2A) - 4 (A2A-) Always 10 kΩ or higher

    3. Reconnect the air fuel ratio sensor connector.


    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  11. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)


    1. A0160F6E03

      Disconnect the air fuel ratio sensor connectors.

    2. Disconnect the ECM connectors.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      E42-1 (HA1A) - E6-5 (HA1A) Always Below 1 Ω
      E42-3 (A1A+) - E5-23 (A1A+) Always Below 1 Ω
      E42-4 (A1A-) - E5-22 (A1A-) Always Below 1 Ω
      E38-1 (HA2A) - E6-6 (HA2A) Always Below 1 Ω
      E38-3 (A2A+) - E5-21 (A2A+) Always Below 1 Ω
      E38-4 (A2A-) - E5-20 (A2A-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      E42-1 (HA1A) or E6-5 (HA1A) - Body ground Always 10 kΩ or higher
      E42-3 (A1A+) or E5-23 (A1A+) - Body ground Always 10 kΩ or higher
      E42-4 (A1A-) or E5-22 (A1A-) - Body ground Always 10 kΩ or higher
      E38-1 (HA2A) or E6-6 (HA2A) -Body ground Always 10 kΩ or higher
      E38-3 (A2A+) or E5-21 (A2A+) - Body ground Always 10 kΩ or higher
      E38-4 (A2A-) or E5-20 (A2A-) - Body ground Always 10 kΩ or higher

    4. Reconnect the air fuel ratio sensor connectors.

    5. Reconnect the ECM connectors.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  12. REPLACE AIR FUEL RATIO SENSOR


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  13. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

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

    3. Clear DTCs Click here.

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

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

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


    NEXT

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


    1. Enter the following menus: Powertrain / Engine / DTC / Pending.

    2. Read the pending DTCs.

      Result
      Display (DTC output) Proceed to
      P0171, P0172, P0174, P0175, P1170 or P117B A
      No 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 Click here

    A

  16. CHECK FUEL PUMP OPERATION


    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

    OK

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

  18. CHECK FUEL PRESSURE SENSOR


    1. Connect the intelligent tester to the DLC3.

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

    3. Start the engine.

    4. Enter the following menus: Powertrain / Engine / Data List / Fuel Press.

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

      Standard
      Idling
      3000 to 5000 kPa
      2000 rpm (No load)
      7000 to 9000 kPa

      Tech Tips

      The A/C switch and all accessory switches should be OFF, and the transmission gear selector 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 INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.

      Tech Tips

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

    4. Read the value.


      1. Enter the following menus: Data List / All Data / 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
        40% or more -20% or less -20% or less A
        10% or less +20% or more +20% or more A
        40% or more +20% or more +20% or more B
        10% or less -20% or less -20% or less C
        10% to 40% - - D

    A

    REPLACE FUEL PRESSURE SENSOR Click here

    B

    INSPECT FUEL RELIEF VALVE Click here

    C

    REPLACE ECM Click here

    D

  20. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and turn the tester on.

    3. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.

      Tech Tips

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

    4. Read the value of Data List.


      1. Enter the following menus: Data List / All Data / 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

    B

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

    C

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

    D

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

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

  21. CHECK MISFIRE COUNT


    1. Connect the intelligent tester to the DLC3.

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

    3. Start the engine.

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

    5. Allow the engine to idle.

    6. Monitor all of the misfire count values that are displayed on the tester: Powertrain / Engine / Data List / All Data / Cylinder #1 Misfire Count to Cylinder #8 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 tester.

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

    B

    REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) Click here

    A

  22. INSPECT INJECTOR DRIVER (NO. 1 AND NO. 2)


    1. Turn the engine switch off.

    2. Replace the No. 1 and No. 2 injector drivers 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.

    3. Connect the intelligent tester to the DLC3.

    4. Start the engine.

    5. Clear DTCs Click here.

    6. Perform the driving test.

    7. Enter the following menus: Powertrain / Engine / DTC / Pending.

    8. Read the pending DTCs.

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

    B

    REPLACE INJECTOR DRIVER (NO. 1 AND NO. 2) Click here

    A

  23. INSPECT FUEL RELIEF VALVE


    1. Connect the intelligent tester to the DLC3.

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

    3. Start the engine.

    4. Enter the following menus: Powertrain / Engine / Data List / Fuel Press.

    5. Write down the Fuel Press value.

    6. Turn the engine switch off.

    7. Wait for 10 seconds.

    8. Turn the engine switch on (IG) and turn the tester on.

    9. Enter the following menus: Powertrain / Engine / Data List / Fuel Press.

    10. Compare the Fuel Press value and the fuel pressure value after the engine switch was turned on (IG).

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

    B

    REPLACE FUEL RELIEF VALVE Click here

    A

    REPLACE FUEL PUMP FOR HIGH PRESSURE Click here

  24. CHECK FUEL INJECTOR FOR PORT INJECTION


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


    NG

    REPLACE FUEL INJECTOR FOR PORT INJECTION Click here

    OK

    REPLACE ECM Click here

  25. CHECK HARNESS AND CONNECTOR


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

      Tech Tips

      Repair any problems.


    NEXT

  26. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the engine switch off.

    6. Turn the engine switch on (IG) and turn the tester on.

    7. Start the engine and warm it up.

    8. 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 OR P117B)


    1. Enter the following menus: Powertrain / Engine / DTC / Pending.

    2. Read the pending DTCs.

      Result
      Display (DTC output) Proceed to
      P0171, P0172, P0174, P0175, P1170 or P117B A
      No output B

    B

    END

    A

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


    1. Disconnect the mass air flow meter connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance between the terminals.

      Standard resistance (Check for Open)
      Tester Connection Condition Specified Condition
      E29-5 (VG) - E3-25 (VG) Always Below 1 Ω
      E29-4 (E2G) - E3-24 (E2G) Always Below 1 Ω
      Standard resistance (Check for Short)
      Tester Connection Condition Specified Condition
      E29-5 (VG) or E3-25 (VG) - Body ground Always 10 kΩ or higher

    4. Reconnect the mass air flow meter connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  29. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY


    1. Replace the mass air flow meter 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 assembly.


    NEXT

  30. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the engine switch off.

    6. Turn the engine switch on (IG) and turn the tester on.

    7. Start the engine and warm it up.

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


    NEXT

  31. CHECK MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Enter the following menus: Powertrain / Engine / DTC / Pending.

    2. Read the pending DTCs.

      Result
      Display (DTC output) Proceed to
      P0171, P0172, P0174, P0175, P1170 or P117B A
      No output B

    B

    END

    A

    REPLACE ECM Click here