DTC P0300: Random / Multiple Cylinder Misfire Detected (TO 12/2010); DTC P0301: Cylinder 1 Misfire Detected (TO 12/2010); DTC P0302: Cylinder 2 Misfire Detected (TO 12/2010); DTC P0303: Cylinder 3 Misfire Detected (TO 12/2010); DTC P0304: Cylinder 4 Misfire Detected (TO 12/2010); DTC P0305: Cylinder 5 Misfire Detected (TO 12/2010); DTC P0306: Cylinder 6 Misfire Detected (TO 12/2010): Procedure

1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine / Trouble Codes.
5. Read the DTCs.

   HINT: 

   Write down the DTCs.

   Result

   Result	Proceed to
   DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 is output	A
   DTC P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 and other DTCs are output	B

   HINT: 

   If any DTCs other than P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 are output, troubleshoot those DTCs first.

B → See step   38 

A: Go to next step 

1. Check the PCV hose connections.

   OK

   PCV hose is correctly connected and is not damaged.

NG → REPAIR OR REPLACE PCV HOSE 

OK: Go to next step 

1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Enter the following menus: Powertrain / Engine / Data List / All Data / Misfire RPM and Misfire Load.
4. Read and note the Misfire RPM and Misfire Load values.

   HINT: 

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

NEXT: Go to next step 

1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Enter the following menus: Powertrain / Engine / Data List / All Data / Catalyst OT MF F/C.
4. Read the value displayed on the Techstream.

   Result

   Data List	Techstream Display	Proceed to
   Catalyst OT MF F/C	Avail	A
   	Not Avl	B

B → See step   6 

A: Go to next step 

1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Enter the following menus: Powertrain / Engine / Active Test / Prohibit the Catalyst OT Misfire prevent F/C.
4. 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 or less.

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Enter the following menus: Powertrain / Engine / Data List / All Data / Cylinder #1 Misfire Count, #2, #3, #4, #5 and #6
4. Read each value for Cylinder #1 Misfire Count to #6 displayed on the Techstream. If no misfire counts occur in any cylinders, perform the following procedures:
   1. Start the engine and let it idle.
   2. Move the shift lever to the D.
   3. Check the Cylinder #1 Misfire Count to #6.
   4. If misfire counts are still not displayed, perform steps [A] and [B].
5. Drive the vehicle with the Misfire RPM and Misfire Load noted in the "READ VALUE OF TECHSTREAM (MISFIRE RPM AND MISFIRE LOAD)" procedures above [A].
6. Read the Cylinder #1 Misfire Count to #6 or DTCs displayed on the Techstream [B].

   Result

   Result	Proceed to
   Most misfires occur in only 1 or 2 cylinders	A
   3 cylinders or more have equal misfire counts	B

   HINT: 

   • 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's 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's record of the Engine Run Time is below 120 seconds, the misfire may be detected immediately after the engine is started.

B → See step   18 

A: Go to next step 

1. Remove the ignition coil and the spark plug of the misfiring cylinder.
   Fig 1: Identifying Spark Plug Electrode Gap

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the spark plug electrode gap.

   Electrode Gap for New Spark Plug

   1.0 to 1.1 mm (0.0394 to 0.0433 in.)

   Maximum Electrode Gap for Used Spark Plug

   1.4 mm (0.0551 in.)

   NOTE:

   If the electrode gap is more than the maximum, replace the spark plug. Do not adjust the electrode gap.

3. Check the electrode for carbon deposits.
   RECOMMENDED SPARK PLUG:
   
   

   Manufacturer	Product
   DENSO	FK20HR11

4. Reinstall the ignition coil and spark plug.

NG → REPLACE SPARK PLUG 

OK: Go to next step 

1. Disconnect the fuel injector assembly connectors to prevent the engine from starting.
   WARNING:

   Always disconnect all fuel injector assembly connectors.

   NOTE:

   Do not crank the engine for more than 2 seconds.

2. Remove the ignition coil from the cylinder head.
3. Install the spark plug onto the ignition coil.
4. Attach the spark plug assembly to the cylinder head.
5. Crank the engine for less than 2 seconds and check the spark.

   OK

   Sparks jump across electrode gap.

6. Install the ignition coil.
7. Reconnect the fuel injector assembly connectors.

NG → See step   34 

OK: Go to next step 

1. Measure the cylinder compression pressure of the misfiring cylinder. Refer to ON-VEHICLE INSPECTION - Step 4 .

NG → CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION 

OK: Go to next step 

1. Disconnect the fuel injector assembly connector (of the misfiring cylinder).
   Fig 2: Identifying Fuel Injector Assembly Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   B39-2 - Body ground	Ignition switch ON	11 to 14 V
   B27-2 - Body ground	Ignition switch ON	11 to 14 V
   B40-2 - Body ground	Ignition switch ON	11 to 14 V
   B28-2 - Body ground	Ignition switch ON	11 to 14 V
   B41-2 - Body ground	Ignition switch ON	11 to 14 V
   B29-2 - Body ground	Ignition switch ON	11 to 14 V

4. Reconnect the fuel injector assembly connector.

NG → See step   37 

OK: Go to next step 

1. Disconnect the fuel injector assembly 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
   B50-45 (#10) - B39-1	Always	Below 1 Ω
   B50-85 (#20) - B27-1	Always	Below 1 Ω
   B50-44 (#30) - B40-1	Always	Below 1 Ω
   B50-84 (#40) - B28-1	Always	Below 1 Ω
   B50-43 (#50) - B41-1	Always	Below 1 Ω
   B50-83 (#60) - B29-1	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B50-45 (#10) or B39-1 - Body ground	Always	10 kΩ or higher
   B50-85 (#20) or B27-1 - Body ground	Always	10 kΩ or higher
   B50-44 (#30) or B40-1 - Body ground	Always	10 kΩ or higher
   B50-84 (#40) or B28-1 - Body ground	Always	10 kΩ or higher
   B50-43 (#50) or B41-1 - Body ground	Always	10 kΩ or higher
   B50-83 (#60) or B29-1 - Body ground	Always	10 kΩ or higher

4. Reconnect the fuel injector assembly connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM) 

OK: Go to next step 

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

NG → See step   39 

OK: Go to next step 

1. Check the air induction system for vacuum leakage.

   OK

   No leakage from air induction system.

NG → REPAIR OR REPLACE AIR INDUCTION SYSTEM 

OK: Go to next step 

1. Check the fuel pressure. Refer to ON-VEHICLE INSPECTION - Step 2 .

NG → See step   36 

OK: Go to next step 

NG → REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine / Data List / All Data / MAF and Coolant Temp.
5. Start the engine and warm it up.
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 g/sec. and 17 g/sec. (shift lever: N; A/C: Off).

NG → See step   29 

OK: Go to next step 

OK → See step   29 

NG → ADJUST VALVE TIMING 

1. Check the air induction system for vacuum leakage.

   OK

   No leakage from air induction system.

NG → REPAIR OR REPLACE AIR INDUCTION SYSTEM 

OK: Go to next step 

1. Check the fuel pressure. Refer to ON-VEHICLE INSPECTION - Step 2 .

NG → See step   36 

OK: Go to next step 

NG → REPLACE ENGINE COOLANT TEMPERATURE SENSOR 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine / Data List / All Data / MAF and Coolant Temp.
5. Start the engine and warm it up.
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 g/sec. and 17 g/sec. (shift lever: N; A/C: Off).

NG → See step   29 

OK: Go to next step 

NG → ADJUST VALVE TIMING 

OK: Go to next step 

1. Remove the ignition coil and the spark plug of the misfiring cylinder.
   Fig 3: Identifying Spark Plug Electrode Gap

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the spark plug electrode gap.

   Electrode Gap for New Spark Plug

   1.0 to 1.1 mm (0.0394 to 0.0433 in.)

   Maximum Electrode Gap for Used Spark Plug

   1.4 mm (0.0551 in.)

   NOTE:

   If the electrode gap is more than the maximum, replace the spark plug. Do not adjust the electrode gap.

3. Check the electrode for carbon deposits.
   RECOMMENDED SPARK PLUG:
   
   

   Manufacturer	Product
   DENSO	FK20HR11

4. Reinstall the ignition coil and spark plug.

NG → REPLACE SPARK PLUG 

OK: Go to next step 

1. Disconnect the fuel injector assembly connectors to prevent the engine from starting.
   WARNING:

   Always disconnect all fuel injector assembly connectors.

   NOTE:

   Do not crank the engine for more than 2 seconds.

2. Remove the ignition coil from the cylinder head.
3. Install the spark plug onto the ignition coil.
4. Attach the spark plug assembly to the cylinder head.
5. Crank the engine for less than 2 seconds and check the spark.

   OK

   Sparks jump across electrode gap.

6. Install the ignition coil.
7. Reconnect the fuel injector assembly connectors.

NG → See step   34 

OK: Go to next step 

1. Measure the cylinder compression pressure of the misfiring cylinder. Refer to ON-VEHICLE INSPECTION - Step 4 .

NG → CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION 

OK: Go to next step 

1. Disconnect the fuel injector assembly connector (of the misfiring cylinder).
   Fig 4: Identifying Fuel Injector Assembly Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   B39-2 - Body ground	Ignition switch ON	11 to 14 V
   B27-2 - Body ground	Ignition switch ON	11 to 14 V
   B40-2 - Body ground	Ignition switch ON	11 to 14 V
   B28-2 - Body ground	Ignition switch ON	11 to 14 V
   B41-2 - Body ground	Ignition switch ON	11 to 14 V
   B29-2 - Body ground	Ignition switch ON	11 to 14 V

4. Reconnect the fuel injector assembly connector.

NG → See step   37 

OK: Go to next step 

1. Disconnect the fuel injector assembly 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
   B50-45 (#10) - B39-1	Always	Below 1 Ω
   B50-85 (#20) - B27-1	Always	Below 1 Ω
   B50-44 (#30) - B40-1	Always	Below 1 Ω
   B50-84 (#40) - B28-1	Always	Below 1 Ω
   B50-43 (#50) - B41-1	Always	Below 1 Ω
   B50-83 (#60) - B29-1	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B50-45 (#10) or B39-1 - Body ground	Always	10 kΩ or higher
   B50-85 (#20) or B27-1 - Body ground	Always	10 kΩ or higher
   B50-44 (#30) or B40-1 - Body ground	Always	10 kΩ or higher
   B50-84 (#40) or B28-1 - Body ground	Always	10 kΩ or higher
   B50-43 (#50) or B41-1 - Body ground	Always	10 kΩ or higher
   B50-83 (#60) or B29-1 - Body ground	Always	10 kΩ or higher

4. Reconnect the fuel injector assembly connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM) 

OK: Go to next step 

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

NG → See step   39 

OK: Go to next step 

1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM. Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE .

   HINT: 

   Repair any problems.

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Clear the DTCs. Refer to DTC CHECK / CLEAR .
5. Turn the ignition switch off.
6. Turn the ignition switch to ON and turn the Techstream on.
7. Start the engine and warm it up.
8. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
9. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
10. Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305 or P0306.
11. Check the DTC judgment result.
    RESULT
    
    

    Result	Proceed to
    ABNORMAL (DTC P0300, P0301, P0302, P0303, P0304, P0305 or P0306 is output)	A
    NORMAL (DTC is not output)	B

B → END 

A: Go to next step 

1. Disconnect the mass air flow 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
   B50-72 (VG) - B10-5 (VG)	Always	Below 1 Ω
   B50-73 (E2G) - B10-4 (E2G)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B50-72 (VG) or B10-5 (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: Go to next step 

1. Replace the mass air flow meter.

   HINT: 

   If the results of the inspections performed in steps 16 and 21 indicated no problem, proceed to the next step without replacing the mass air flow meter.

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Clear the DTCs. Refer to DTC CHECK / CLEAR .
5. Turn the ignition switch off.
6. Turn the ignition switch to ON and turn the Techstream on.
7. Start the engine and warm it up.
8. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
9. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
10. Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305 or P0306.
11. Check the DTC judgment result.
    RESULT
    
    

    Result	Proceed to
    NORMAL (DTC is not output)	A
    ABNORMAL (DTC P0300, P0301, P0302, P0303, P0304, P0305 or P0306 is output)	B

B → See step   40 

A → END 

1. Change the installed spark plug to a spark plug that functions normally.
2. Perform a spark test.
   WARNING:

   Always disconnect all injector connectors.

   NOTE:

   Do not crank the engine for more than 2 seconds.

   1. Install the spark plug to the ignition coil and connect the ignition coil connector.
   2. Disconnect the injector connector.
   3. Ground the spark plug.
   4. Check if sparks occur while the engine is being cranked.

      OK

      Sparks jump across electrode gap.

NG → See step   35 

OK → REPLACE SPARK PLUG 

1. Change the ignition coil to a ignition coil that functions normally.
2. Perform a spark test.
   WARNING:

   Always disconnect all injector connectors.

   NOTE:

   Do not crank the engine for more than 2 seconds.

   1. Install the spark plug into the ignition coil and connect the ignition coil connector.
   2. Disconnect the injector connector.
   3. Ground the spark plug.
   4. Check if sparks occur while the engine is being cranked.

      OK

      Sparks jump across electrode gap.

NG → See step   40 

OK → REPLACE IGNITION COIL 

1. Check the fuel lines for leaks or blockage.

NG → REPAIR OR REPLACE FUEL LINE 

OK → See step   41 

1. Disconnect the fuel injector assembly connector.
2. Remove the IG2 relay from the engine room relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   B39-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω
   B27-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω
   B40-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω
   B28-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω
   B41-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω
   B29-2 - 2 (IG2 relay terminal)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   B39-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher
   B27-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher
   B40-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher
   B28-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher
   B41-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher
   B29-2 or 2 (IG2 relay terminal) - Body ground	Always	10 kΩ or higher

4. Reinstall the IG2 relay.
5. Reconnect the fuel injector assembly connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - FUEL INJECTOR ASSEMBLY) 

OK → See step   42