SFI SYSTEM, Diagnostic DTC:P0300,P0301,P0302,P0303 and P0304

DTC Code DTC Name
P0300 Random / Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected

DESCRIPTION

When the engine misfires, high concentrations of hydrocarbons (HC) enter the exhaust gas. Extremely high hydrocarbon concentration levels can cause an increase in exhaust emission levels. Extremely high concentrations of hydrocarbons can also cause increases in the three-way catalytic converter temperature, which may cause damage to the three-way catalytic converter. To prevent this increase in emissions and to limit the possibility of thermal damage, the ECM monitors the misfire count. When the temperature of the three-way catalytic converter reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the camshaft position sensor and the crankshaft position sensor. The camshaft position sensor is used to identify any misfiring cylinders and the crankshaft position sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted when the crankshaft rotation speed variations exceed predetermined thresholds. If the misfire count exceeds the threshold levels, and could cause emission control system performance deterioration, the ECM illuminates the MIL and stores a DTC.

A256637E03

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0300

Random / Multiple Cylinder Misfire Detected

Simultaneous misfiring of several cylinders occurs and one of the following conditions is met (2 trip detection logic):

  • A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).

  • An emission deterioration misfire occurs (MIL illuminates).

  • Open or short in engine wire harness

  • Connector connection

  • Vacuum hose connections

  • Ignition system

  • Fuel injector assembly

  • Fuel pressure

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Compression pressure

  • Valve timing

  • PCV valve and hose

  • PCV hose connections

  • Intake system

  • EGR valve assembly

  • ECM

Comes on/Blinks* (Euro-OBD) / - (except Euro-OBD)

*: The MIL flashes when a catalyst-damaging misfire is detected.

DTC stored (Euro-OBD) / - (except Euro-OBD)

P0301

Cylinder 1 Misfire Detected

Misfiring of the No. 1 cylinder occurs and one of the following conditions is met (2 trip detection logic):

  • A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).

  • An emission deterioration misfire occurs (MIL illuminates).

  • Open or short in engine wire harness

  • Connector connection

  • Vacuum hose connections

  • Ignition system

  • Fuel injector assembly

  • Fuel pressure

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Compression pressure

  • Valve timing

  • PCV valve and hose

  • PCV hose connections

  • Intake system

  • EGR valve assembly

  • ECM

Comes on/Blinks* (Euro-OBD) / - (except Euro-OBD)

*: The MIL flashes when a catalyst-damaging misfire is detected.

DTC stored (Euro-OBD) / - (except Euro-OBD)

P0302

Cylinder 2 Misfire Detected

Misfiring of the No. 2 cylinder occurs and one of the following conditions is met (2 trip detection logic):

  • A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).

  • An emission deterioration misfire occurs (MIL illuminates).

  • Open or short in engine wire harness

  • Connector connection

  • Vacuum hose connections

  • Ignition system

  • Fuel injector assembly

  • Fuel pressure

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Compression pressure

  • Valve timing

  • PCV valve and hose

  • PCV hose connections

  • Intake system

  • EGR valve assembly

  • ECM

Comes on/Blinks* (Euro-OBD) / - (except Euro-OBD)

*: The MIL flashes when a catalyst-damaging misfire is detected.

DTC stored (Euro-OBD) / - (except Euro-OBD)

P0303

Cylinder 3 Misfire Detected

Misfiring of the No. 3 cylinder occurs and one of the following conditions is met (2 trip detection logic):

  • A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).

  • An emission deterioration misfire occurs (MIL illuminates).

  • Open or short in engine wire harness

  • Connector connection

  • Vacuum hose connections

  • Ignition system

  • Fuel injector assembly

  • Fuel pressure

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Compression pressure

  • Valve timing

  • PCV valve and hose

  • PCV hose connections

  • Intake system

  • EGR valve assembly

  • ECM

Comes on/Blinks* (Euro-OBD) / - (except Euro-OBD)

*: The MIL flashes when a catalyst-damaging misfire is detected.

DTC stored (Euro-OBD) / - (except Euro-OBD)

P0304

Cylinder 4 Misfire Detected

Misfiring of the No. 4 cylinder occurs and one of the following conditions is met (2 trip detection logic):

  • A misfire occurs that may damage the three-way catalytic converter (MIL blinks when detect immediately).

  • An emission deterioration misfire occurs (MIL illuminates).

  • Open or short in engine wire harness

  • Connector connection

  • Vacuum hose connections

  • Ignition system

  • Fuel injector assembly

  • Fuel pressure

  • Mass air flow meter sub-assembly

  • Engine coolant temperature sensor

  • Compression pressure

  • Valve timing

  • PCV valve and hose

  • PCV hose connections

  • Intake system

  • EGR valve assembly

  • ECM

Comes on/Blinks* (Euro-OBD) / - (except Euro-OBD)

*: The MIL flashes when a catalyst-damaging misfire is detected.

DTC stored (Euro-OBD) / - (except Euro-OBD)

When DTCs for misfiring cylinders are randomly stored, but DTC P0300 is not stored, it indicates that misfires have been detected in different cylinders at different times. DTC P0300 is only stored when several misfiring cylinders are detected at the same time.

MONITOR DESCRIPTION

The ECM illuminates the MIL and stores a DTC when the following condition, which could cause emission deterioration, is detected (2 trip detection logic).

  • An excessive number of misfires (approximately 60 to 70 misfires per 1000 crankshaft revolutions) occurs a total of 4 times.

The ECM flashes the MIL (immediate detection logic) and stores a DTC (2 trip detection logic) when the following condition, which could cause damage to the three-way catalytic converter, is detected.

  • At a normal engine speed, a sufficient amount of misfires to damage the catalyst occurring within 200 crankshaft revolutions is detected 3 times.

MONITOR STRATEGY

Required Sensors/Components (Main)

Crankshaft position sensor

Camshaft position sensor

Required Sensors/Components (Related)

Engine coolant temperature sensor

Intake air temperature sensor

Mass air flow meter sub-assembly

Frequency of Operation

Continuous

TYPICAL ENABLING CONDITIONS

Table 1. Misfire

Intake air temperature

Higher than -10°C (14°F)

Either of the following conditions is met

(a) or (b)

(a) Engine coolant temperature at engine start

Higher than -7°C (19°F)

(b) Engine coolant temperature

Higher than 20°C (68°F)
Table 2. Monitor Period of Emission-related Misfire

Duration

1000 crankshaft revolutions x 4
Table 3. Monitor Period of Catalyst-damaging Misfire (MIL Blinks)

Duration

200 crankshaft revolutions x 3

CONFIRMATION DRIVING PATTERN

  1. Connect the GTS to the DLC3.

  2. Turn the ignition switch to ON.

  3. Turn the GTS on.

  4. Record the DTC(s) and freeze frame data.

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

  6. Using the GTS, switch the ECM from normal mode to check mode.

    Click here

  7. Read the misfire counts of each cylinder, Cylinder #1 Misfire Count to Cylinder #4 Misfire Count, with the engine idling. If any misfire count is displayed, skip the following confirmation driving pattern.

  8. Drive the vehicle so that the vehicle conditions displayed in Misfire RPM and Misfire Load of the Data List are the same as the freeze frame data. Perform this step several times.

    Tip:

    In order to store misfire DTCs, it is necessary to operate the vehicle for the period of time shown in the table below, confirm the Misfire RPM and Misfire Load in the Data List.

    Engine speed

    Duration

    Idling

    8.0 minutes or more

    1000

    4.5 minutes or more

    2000

    2.5 minutes or more

    3000

    1.5 minutes or more

  9. Check whether misfires have occurred by checking DTCs and freeze frame data.

    Tip:

    Do not turn the ignition switch off until the output DTC(s) and freeze frame data have been recorded. When the ECM returns to normal mode (default), the stored DTC(s), freeze frame data and other data are cleared.

  10. Record the DTC(s), freeze frame data and misfire counts.

  11. Turn the ignition switch off and wait for at least 30 seconds.

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

WIRING DIAGRAM

Refer to DTC P0102.

Click here

Refer to Fuel Injector Circuit.

Click here

CAUTION / NOTICE / HINT

Tip:

  • If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.

  • 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 help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  • If the misfire does not recur when the vehicle is brought to the workshop, reproduce the conditions stored in the ECM as freeze frame data.

  • If the misfire still cannot be reproduced even though the conditions stored in the ECM as freeze frame data have been reproduced, one of the following factors is considered to be a possible cause of the problem:

    1. There was insufficient fuel in the tank.

    2. Improper fuel was used.

    3. The spark plugs have been contaminated.

    4. The problem requires further diagnosis.

  • After finishing repairs, check the misfire counts of the cylinders (Cylinder #1 Misfire Count to Cylinder #4 Misfire Count).

  • Be sure to confirm that no misfiring cylinder DTCs are stored again by conducting the confirmation driving pattern after finishing repairs.

  • When one of Short FT #1 or Long FT #1 in the freeze frame data is outside the range of +/-15%, the air fuel ratio may be rich (-15% or less) or lean (+15% or higher).

  • When Coolant Temp in the freeze frame data is below 75°C (167°F), the misfires have occurred only while warming up the engine.

  • An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be stored.

  • Check the "Fuel Cut Elps Time" in the Data List or the Freeze Frame Data.

    If the elapsed time is over 0 seconds, then the engine speed is high (engine speed at which fuel cut occurs + 500 rpm).

    When this has happened, there is the possibility that the No. 1 valve rocker arm sub-assembly will become loose and a fire could start, so check that the No. 1 valve rocker arm sub-assembly is properly attached.

    Click here

  • By clearing the DTC, "Fuel Cut Elps Time" will be cleared.

  • In the past, when the primary ignition system (the igniter drive circuit in the ECM, the primary circuit in the No. 1 ignition coil, the related wire harness, or the connector) was out of order, diagnostic codes from P0351 to P0354 were output. However, these codes are not output in this vehicle.

    When a failure in the primary ignition system is suspected, refer to "Cat OT MF F/C History", "Cat OT MF F/C Cylinder #1 to #4", and "Cylinder #1 Misfire Count to Cylinder #4 Misfire Count" in the freeze frame data, the pending freeze frame data, and the Data List, and confirm in which cylinder the high-frequency misfire was concentrated.

Note:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO MISFIRE DTCS)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Read the DTCs.

      Powertrain > Engine and ECT > Trouble Codes

      Result

      Result

      Proceed to

      DTC P0300, P0301, P0302, P0303 and/or P0304 are output

      A

      DTC P0300, P0301, P0302, P0303 and/or P0304 and other DTCs are output

      B
      Tip:

      If any DTCs other than P0300, P0301, P0302, P0303 and P0304 are output, troubleshoot those DTCs first.

    B

    GO TO DTC CHART

    Click here

    A

  2. CHECK PCV HOSE CONNECTIONS

    1. Check the PCV hose connections.

      Click here

      OK

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

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE PCV HOSE

    OK

  3. READ VALUE USING GTS (MISFIRE RPM AND MISFIRE LOAD)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Misfire RPM and Misfire Load.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Misfire RPM

      Misfire Load

    5. Read and note the Misfire RPM and Misfire Load values.

      Tip:

      The Misfire RPM and Misfire Load values indicate the vehicle conditions under which the misfire occurred.

    Result

    Proceed to

    NEXT
    NEXT

  4. READ FREEZE FRAME DATA

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Using the GTS, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored.

      Click here

    Result

    Freeze Frame Data Item

    Result

    Proceed to

    Cat OT MF F/C History

    ON

    A

    OFF

    B
    B

    PERFORM ACTIVE TEST USING GTS (PROHIBIT THE CATALYST OT MISFIRE PREVENT F/C)Click here

    A

  5. INSPECT SPARK PLUG

    1. Inspect the spark plug of the misfiring cylinder.

      Click here

      Tip:

      • According to the "Cat OT MF F/C Cylinder #1 to #4" on the Data List, check the spark plug of the malfunctioning cylinder.

      • Perform "Inspection After Repair" after replacing the spark plug.

        Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE SPARK PLUG

    Click here

    OK

  6. CHECK FOR SPARK (SPARK TEST)

    1. Perform a spark test.

      Click here

      Tip:

      • If the result of the spark test is normal, proceed to the next step.

      • Perform "Inspection After Repair" after repairing or replacing the ignition system.

        Click here

    Result

    Proceed to

    NEXT
    NEXT

  7. PERFORM ACTIVE TEST USING GTS (PROHIBIT THE CATALYST OT MISFIRE PREVENT F/C)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Prohibit the Catalyst OT Misfire prevent F/C.

      Powertrain > Engine and ECT > Active Test

      Tester Display

      Prohibit the Catalyst OT Misfire prevent F/C

    6. Perform the Active Test.

      Note:

      When performing the Active Test, make sure the vehicle is stopped and the engine is either idling or being revved within 3000 rpm.

    Result

    Proceed to

    NEXT
    NEXT

  8. READ VALUE USING GTS (CYLINDER MISFIRE COUNT)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Cylinder #1 Misfire Count, Cylinder #2 Misfire Count, Cylinder #3 Misfire Count and Cylinder #4 Misfire Count.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Cylinder #1 Misfire Count

      Cylinder #2 Misfire Count

      Cylinder #3 Misfire Count

      Cylinder #4 Misfire Count

    5. Start the engine and allow the engine to idle.

    6. Read each value for Cylinder #1 Misfire Count to Cylinder #4 Misfire Count displayed on the GTS. If no misfire counts occur in any cylinders, perform procedure [A] and [B] and then check the misfire counts again.

    7. Drive the vehicle with the Misfire RPM and Misfire Load noted in the "Read Value Using GTS (Misfire RPM and Misfire Load)" procedures above [A].

    8. Read the Cylinder #1 Misfire Count to Cylinder #4 Misfire Count or DTCs displayed on the GTS [B].

      Result

      Result

      Proceed to

      Most misfires occur in only 1 or 2 cylinders

      A

      3 cylinders or more have equal misfire counts

      B
      Tip:

      • If it is difficult to reproduce misfires for each cylinder, check the Data List item called Misfire Margin. Try to find vehicle driving conditions that lower the Misfire Margin value. Values above 30% are considered normal.

      • If the freeze frame data record of the engine coolant temperature is below 75°C (167°F), the misfire may be detected only when the engine is cold.

      • If the freeze frame data record of the Engine Run Time is below 120 seconds, the misfire may be detected immediately after the engine is started.

    B

    CHECK INTAKE SYSTEMClick here

    A

  9. INSPECT SPARK PLUG

    1. Inspect the spark plug of the misfiring cylinder.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the spark plug.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE SPARK PLUG

    Click here

    OK

  10. CHECK FOR SPARK (SPARK TEST)

    1. Perform a spark test.

      Click here

      Tip:

      • If the result of the spark test is normal, proceed to the next step.

      • Perform "Inspection After Repair" after repairing or replacing the ignition system.

        Click here

    Result

    Proceed to

    NEXT
    NEXT

  11. CHECK CYLINDER COMPRESSION PRESSURE

    1. Measure the cylinder compression pressure of the misfiring cylinder.

      Click here

      Tip:

      Perform "Inspection After Repair" after repairing or replacing the engine assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

    OK

  12. CHECK TERMINAL VOLTAGE (#10, #20, #30 AND/OR #40)

    1. A255689C29

      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      B31-20 (#10) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-17 (#20) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-18 (#30) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-19 (#40) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FUEL INJECTOR CIRCUIT

    Click here

    OK

  13. CHECK FUEL INJECTOR OF MISFIRING CYLINDER

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

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the fuel injector assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE FUEL INJECTOR ASSEMBLY

    Click here

    OK

  14. CHECK INTAKE SYSTEM

    1. Check the intake system for vacuum leaks.

      Click here

      OK

      No leaks from intake system.

      Tip:

      Perform "Inspection After Repair" after repairing or replacing the intake system.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  15. CHECK FUEL PRESSURE

    1. Check the fuel pressure.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FUEL LINEClick here

    OK

  16. READ VALUE USING GTS (COOLANT TEMP)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Coolant Temp

    5. Read the Data List twice, when the engine is both cold and warmed up.

      Standard

      GTS Display

      Condition

      Specified Condition

      Coolant Temp

      Cold engine

      Same as ambient air temperature

      Warm engine

      Between 75 and 100°C (167 and 212°F)
      Tip:

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

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR

    Click here

    OK

  17. READ VALUE USING GTS (MAF)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Engine Speed

      MAF

      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

      GTS Display

      Condition

      Specified Condition

      MAF

      Shift lever position: Neutral

      A/C: Off

      Engine Speed: 3000 rpm

      Between 3.0 gm/sec and 8.0 gm/sec

    Result

    Proceed to

    OK

    NG
    NG

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

    OK

  18. CHECK VALVE TIMING (CHECK FOR LOOSE TIMING CHAIN AND JUMPED TEETH)

    A279822C02

    *a

    Timing Mark

    *b

    No. 1 Cylinder at TDC Compression

    1. Remove the cylinder head cover sub-assembly.

      Click here

    2. Turn the crankshaft pulley, and align its groove with the "0" timing mark of the timing chain cover.

    3. Check that the timing marks of the camshaft timing gear assembly and camshaft timing exhaust gear assembly are at the positions shown in the illustration.

      Tip:

      If the timing marks are not as shown, turn the crankshaft one revolution clockwise.

      OK

      Timing marks on camshaft timing gear assembly and camshaft timing exhaust gear assembly are aligned as shown in the illustration.

      Tip:

      If the result is not as specified, check for mechanical malfunctions that may have affected the valve timing, such as a jumped tooth or stretching of the timing chain.

    Result

    Proceed to

    OK

    NG
    NG

    CHECK ENGINE MECHANICAL SYSTEMClick here

    OK

  19. PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or more.

      Tip:

      The A/C switch and all accessory switches should be off.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / All Data / MAP and Throttle Idle Position.

      Powertrain > Engine and ECT > Active Test

      Active Test Display

      Control the EGR Step Position

      Data List Display

      MAP

      Throttle Idle Position

    6. Confirm that the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.

      OK

      MAP and idling condition change in response to EGR step position.

      -

      EGR Step Position (Active Test)

      0 Steps

      0 to 30 Steps

      Idling condition

      Steady idling

      Idling changes from steady to rough idling or engine stalls

      MAP

      (Data List)

      MAP value is 20 to 48 kPa(abs)

      [150 to 360 mmHg(abs)]

      (EGR valve is fully closed)

      MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed
      Tip:

      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      • During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve assembly.

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

  20. INSPECT EGR VALVE ASSEMBLY

    1. Remove the EGR valve assembly.

      Click here

    2. Check if the EGR valve is stuck open.

      OK

      EGR valve is tightly closed.

      Tip:

      Perform "Inspection After Repair" after replacing the EGR valve assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPLACE EGR VALVE ASSEMBLY

    Click here

  21. CHECK INTAKE SYSTEM

    1. Check the intake system for vacuum leaks.

      Click here

      OK

      No leaks from intake system.

      Tip:

      Perform "Inspection After Repair" after repairing or replacing the intake system.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE INTAKE SYSTEM

    OK

  22. CHECK FUEL PRESSURE

    1. Check the fuel pressure.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FUEL LINEClick here

    OK

  23. READ VALUE USING GTS (COOLANT TEMP)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Coolant Temp

    5. Read the Data List twice, when the engine is both cold and warmed up.

      Standard

      GTS Display

      Condition

      Specified Condition

      Coolant Temp

      Cold engine

      Same as ambient air temperature

      Warm engine

      Between 75 and 100°C (167 and 212°F)
      Tip:

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

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR

    Click here

    OK

  24. READ VALUE USING GTS (MAF)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Engine Speed

      MAF

      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

      GTS Display

      Condition

      Specified Condition

      MAF

      Shift lever position: Neutral

      A/C: Off

      Engine Speed: 3000 rpm

      Between 3.0 gm/sec and 8.0 gm/sec

    Result

    Proceed to

    OK

    NG
    NG

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

    OK

  25. CHECK VALVE TIMING (CHECK FOR LOOSE TIMING CHAIN AND JUMPED TEETH)

    A279822C02

    *a

    Timing Mark

    *b

    No. 1 Cylinder at TDC Compression

    1. Remove the cylinder head cover sub-assembly.

      Click here

    2. Turn the crankshaft pulley, and align its groove with the "0" timing mark of the timing chain cover.

    3. Check that the timing marks of the camshaft timing gear assembly and camshaft timing exhaust gear assembly are at the positions shown in the illustration.

      Tip:

      If the timing marks are not as shown, turn the crankshaft one revolution clockwise.

      OK

      Timing marks on camshaft timing gear assembly and camshaft timing exhaust gear assembly are aligned as shown in the illustration.

      Tip:

      If the result is not as specified, check for mechanical malfunctions that may have affected the valve timing, such as a jumped tooth or stretching of the timing chain.

    Result

    Proceed to

    OK

    NG
    NG

    CHECK ENGINE MECHANICAL SYSTEMClick here

    OK

  26. PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or more.

      Tip:

      The A/C switch and all accessory switches should be off.

    5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / All Data / MAP and Throttle Idle Position.

      Powertrain > Engine and ECT > Active Test

      Active Test Display

      Control the EGR Step Position

      Data List Display

      MAP

      Throttle Idle Position

    6. Confirm that the Throttle Idle Position is ON and check the engine idling condition and MAP values in the Data List while performing the Active Test.

      OK

      MAP and idling condition change in response to EGR step position.

      -

      EGR Step Position (Active Test)

      0 Steps

      0 to 30 Steps

      Idling condition

      Steady idling

      Idling changes from steady to rough idling or engine stalls

      MAP

      (Data List)

      MAP value is 20 to 48 kPa(abs)

      [150 to 360 mmHg(abs)]

      (EGR valve is fully closed)

      MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed
      Tip:

      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      • During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve assembly.

    Result

    Proceed to

    OK

    NG
    OK

    INSPECT SPARK PLUGClick here

    NG

  27. INSPECT EGR VALVE ASSEMBLY

    1. Remove the EGR valve assembly.

      Click here

    2. Check if the EGR valve is stuck open.

      OK

      EGR valve is tightly closed.

      Tip:

      Perform "Inspection After Repair" after replacing the EGR valve assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE EGR VALVE ASSEMBLY

    Click here

    OK

  28. INSPECT SPARK PLUG

    1. Remove the No. 1 ignition coil and the spark plug from the misfiring cylinder.

    2. Inspect the spark plug of the misfiring cylinder.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the spark plug.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE SPARK PLUG

    Click here

    OK

  29. CHECK FOR SPARK (SPARK TEST)

    1. Perform a spark test.

      Click here

      Tip:

      • If the result of the spark test is normal, proceed to the next step.

      • Perform "Inspection After Repair" after repairing or replacing the ignition system.

        Click here

    Result

    Proceed to

    NEXT
    NEXT

  30. CHECK CYLINDER COMPRESSION PRESSURE

    1. Measure the cylinder compression pressure of the misfiring cylinder.

      Click here

      Tip:

      Perform "Inspection After Repair" after repairing or replacing the engine assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

    OK

  31. CHECK TERMINAL VOLTAGE (#10, #20, #30 AND/OR #40)

    1. A255689C29

      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      B31-20 (#10) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-17 (#20) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-18 (#30) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

      B31-19 (#40) - B31-51 (E01)

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FUEL INJECTOR CIRCUIT

    Click here

    OK

  32. CHECK FUEL INJECTOR OF MISFIRING CYLINDER

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

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the fuel injector assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPLACE FUEL INJECTOR ASSEMBLY

    Click here

  33. CHECK ENGINE MECHANICAL SYSTEM

    1. Check for mechanical malfunctions that affect the valve timing, such as a jumped tooth or stretching of the timing chain.

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE MALFUNCTIONING PARTS, COMPONENT AND AREA

    OK

  34. CHECK WHETHER DTC OUTPUT RECURS (MISFIRE DTCS)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    5. Turn the ignition switch off and wait for at least 30 seconds.

    6. Turn the ignition switch to ON.

    7. 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 / Utility / All Readiness.

      Powertrain > Engine and ECT > Utility

      Tester Display

      All Readiness

    11. Input the DTC: P0300, P0301, P0302, P0303 or P0304.

    12. Check the DTC judgment result.

    Result

    Result

    Proceed to

    NORMAL

    (DTC is not output)

    A

    ABNORMAL

    (DTC P0300, P0301, P0302, P0303 or P0304 is output)

    B
    A

    CHECK FOR INTERMITTENT PROBLEMS

    Click here

    B

  35. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY CONNECTOR CONNECTION)

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

      Click here

      Tip:

      Repair any problems.

    Result

    Proceed to

    NEXT
    NEXT

  36. CHECK WHETHER DTC OUTPUT RECURS (MISFIRE DTCS)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    5. Turn the ignition switch off and wait for at least 30 seconds.

    6. Turn the ignition switch to ON.

    7. 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 / Utility / All Readiness.

      Powertrain > Engine and ECT > Utility

      Tester Display

      All Readiness

    11. Input the DTC: P0300, P0301, P0302, P0303 or P0304.

    12. Check the DTC judgment result.

    Result

    Result

    Proceed to

    NORMAL

    (DTC is not output)

    A

    ABNORMAL

    (DTC P0300, P0301, P0302, P0303 or P0304 is output)

    B
    A

    END

    B

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

    1. Disconnect the mass air flow meter sub-assembly connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B2-5 (VG) - B31-91 (VG)

      Always

      Below 1 Ω

      B2-4 (E2G) - B31-92 (E2G)

      Always

      Below 1 Ω

      B2-5 (VG) or B31-91 (VG) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  38. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY

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

      Click here

      Tip:

      • If the results of the inspections performed in steps 17 and 24 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 sub-assembly.

        Click here

    Result

    Proceed to

    NEXT
    NEXT

  39. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine and ECT > Clear DTCs

    5. Turn the ignition switch off and wait for at least 30 seconds.

    6. Turn the ignition switch to ON.

    7. 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 / Utility / All Readiness.

      Powertrain > Engine and ECT > Utility

      Tester Display

      All Readiness

    11. Input the DTC: P0300, P0301, P0302, P0303 or P0304.

    12. Check the DTC judgment result.

    Result

    Result

    Proceed to

    NORMAL

    (DTC is not output)

    A

    ABNORMAL

    (DTC P0300, P0301, P0302, P0303 or P0304 is output)

    B
    A

    END

    B

    REPLACE ECM

    Click here

  40. CHECK FUEL LINE

    1. Check the fuel lines for leaks or blockage.

      Tip:

      Perform "Inspection After Repair" after replacing the fuel pump.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE FUEL PUMP

    Click hereClick here

    NG

    REPAIR OR REPLACE FUEL LINE