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

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
3. Turn the tester on.
4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
5. Read DTCs.

   HINT: 

   Write down the DTCs.

   Result

   Display (DTC Output)	Proceed to
   P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306	A
   P0300, P0301, P0302, P0303, P0304, P0305 and/or P0306 and other DTCs	B

   HINT: 

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

B → See step   37 

A: Go to next step 

1. Check the PCV hose connection.

   OK

   PCV hose is correctly connected and is not damaged.

NG → REPAIR OR REPLACE PCV HOSE 

OK: Go to next step 

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

   Result

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

B → See step   6 

A: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG) and turn the tester on.
3. Enter the following menus: Powertrain / Engine and ECT / 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 either idling or being revved within 3000 RPM.

NEXT: Go to next step 

1. Enter the following menus: Powertrain / Engine and ECT / Data List / Misfire / Cylinder #1 Misfire Count, #2, #3, #4, #5 and #6
2. Read each value for Cylinder #1 Misfire Count to #6 displayed on the tester. 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 position.
   3. Check the Cylinder #1 Misfire Count to #6.
   4. If misfire counts are still not displayed, perform steps (c) and (d).
3. Drive the vehicle with the Misfire RPM and Misfire Load noted in the "READ VALUE OF THE TECHSTREAM Misfire RPM AND Misfire Load)" procedures above.
4. Read the Cylinder #1 Misfire Count to #6 or DTCs displayed on the tester.

   Result

   Misfire Count	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 

Fig 1: Identifying Spark Plug

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the ignition coil and the spark plug of the misfiring cylinder.
2. Measure the spark plug electrode gap.

   Maximum gap

   1.4 mm (0.0551 in.)

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

   Manufacturer	Product
   DENSO	FK20HR11

   NOTE:

   If the electrode gap is larger than standard, replace the spark plug. Do not adjust the electrode gap.

NG → See step   38 

OK: Go to next step 

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

   Always disconnect all injector 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 injector 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 .

NG → CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION 

OK: Go to next step 

1. Disconnect the injector connector (of the misfiring cylinder).
   Fig 2: Identifying Injector Connector

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

   Standard voltage

   Cylinder	Tester Connection	Switch Condition	Specified Condition
   No. 1	B13-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 2	B14-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 3	B15-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 4	B16-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 5	B17-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 6	B18-2 - Body ground	Ignition switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Fuel Injector)

NG → GO TO FUEL INJECTOR CIRCUIT 

OK: Go to next step 

1. Turn the ignition switch off.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Check for open 

   Check for short 

   Cylinder	Tester Connection	Condition	Specified Condition
   No. 1	B13-1 - B48-6 (#10)	Always	Below 1 Ω
   No. 2	B14-1 - B48-1 (#20)	Always	Below 1 Ω
   No. 3	B15-1 - B48-7 (#30)	Always	Below 1 Ω
   No. 4	B16-1 - B48-2 (#40)	Always	Below 1 Ω
   No. 5	B17-1 - B48-8 (#50)	Always	Below 1 Ω
   No. 6	B18-1 - B48-3 (#60)	Always	Below 1 Ω

   Cylinder	Tester Connection	Condition	Specified Condition
   No. 1	B13-1 - Body ground	Always	10 kΩ or higher
   No. 2	B14-1 - Body ground	Always	10 kΩ or higher
   No. 3	B15-1 - Body ground	Always	10 kΩ or higher
   No. 4	B16-1 - Body ground	Always	10 kΩ or higher
   No. 5	B17-1 - Body ground	Always	10 kΩ or higher
   No. 6	B18-1 - Body ground	Always	10 kΩ or higher

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

OK: Go to next step 

1. Check the injector resistance, refer to INSPECTION .
2. Check the injector 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, refer to ON-VEHICLE INSPECTION .

   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 .

NG → See step   36 

OK: Go to next step 

NG → See step   40 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
3. Turn the Techstream 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 3000RPM.

   Standard

   Between 10 to 25 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. Check the air induction system for vacuum leakage, refer to ON-VEHICLE INSPECTION .

   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 .

NG → See step   36 

OK: Go to next step 

NG → See step   40 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
3. Turn the Techstream 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 3000RPM.

   Standard

   Between 10 to 25 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 

Fig 3: Identifying Spark Plug

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the ignition coil and the spark plug of the misfiring cylinder.
2. Measure the spark plug electrode gap.

   Maximum gap

   1.4 mm (0.0551 in.)

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

   Manufacturer	Product
   DENSO	FK20HR11

   NOTE:

   If the electrode gap is larger than standard, replace the spark plug. Do not adjust the electrode gap.

NG → See step   38 

OK: Go to next step 

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

   Always disconnect all injector 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 injector 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 .

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

OK: Go to next step 

1. Disconnect the injector connector (of the misfiring cylinder).
   Fig 4: Identifying Injector Connector

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

   Standard voltage

   Cylinder	Tester Connection	Switch Condition	Specified Condition
   No. 1	B13-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 2	B14-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 3	B15-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 4	B16-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 5	B17-2 - Body ground	Ignition switch on (IG)	11 to 14 V
   No. 6	B18-2 - Body ground	Ignition switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Fuel Injector)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (INJ NO. 2 FUSE - INJECTOR) 

OK: Go to next step 

1. Turn the ignition switch off.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Check for open 

   Check for short 

   Cylinder	Tester Connection	Condition	Specified Condition
   No. 1	B13-1 - B48-6 (#10)	Always	Below 1 Ω
   No. 2	B14-1 - B48-1 (#20)	Always	Below 1 Ω
   No. 3	B15-1 - B48-7 (#30)	Always	Below 1 Ω
   No. 4	B16-1 - B48-2 (#40)	Always	Below 1 Ω
   No. 5	B17-1 - B48-8 (#50)	Always	Below 1 Ω
   No. 6	B18-1 - B48-3 (#60)	Always	Below 1 Ω

   Cylinder	Tester Connection	Condition	Specified Condition
   No. 1	B13-1 - Body ground	Always	10 kΩ or higher
   No. 2	B14-1 - Body ground	Always	10 kΩ or higher
   No. 3	B15-1 - Body ground	Always	10 kΩ or higher
   No. 4	B16-1 - Body ground	Always	10 kΩ or higher
   No. 5	B17-1 - Body ground	Always	10 kΩ or higher
   No. 6	B18-1 - Body ground	Always	10 kΩ or higher

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

OK: Go to next step 

1. Check the injector resistance, refer to INSPECTION .
2. Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor), refer to ON-VEHICLE INSPECTION - Step 2 .

NG → See step   39 

OK → See step   41 

1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter and ECM See step  3.

   HINT: 

   Repair any problems.

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
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 on (IG) 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 and ECT / Utility / All Readiness.
10. Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305 or P0306.
11. Check the DTC judgment result.
    RESULT
    
    

    Display (DTC Output)	Proceed to
    ABNORMAL (P0300, P0301, P0302, P0303, P0304, P0305 or P0306 output)	A
    NORMAL (No DTC 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

   Tester Connection	Condition	Specified Condition
   B10-5 (VG) - B50-14 (VG)	Always	Below 1 Ω
   B10-4 (E2G) - B50-13 (E2G)	Always	Below 1 Ω
   B10-5 (VG) or B50-14 (VG) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the mass air flow meter assembly, refer to REMOVAL .

   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 assembly.

NEXT: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch on (IG).
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 on (IG) 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 and ECT / Utility / All Readiness.
10. Input the DTC: P0300, P0301, P0302, P0303, P0304, P0305 or P0306.
11. Check the DTC judgment result.
    RESULT
    
    

    Display (DTC Output)	Proceed to
    NORMAL (No DTC output)	A
    ABNORMAL (P0300, P0301, P0302, P0303, P0304, P0305 or P0306 output)	B

B → See step   41 

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 connectors.
   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 → See step   38 

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

   Always disconnect all fuel 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 fuel injector connectors.
   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   41 

OK → See step   42 

1. Check the fuel lines for leaks or blockage.

NG → REPAIR OR REPLACE FUEL LINE 

OK → REPLACE FUEL PUMP