Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
Read freeze frame data using Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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 freeze frame data.
If the misfire still cannot be reproduced even though the conditions stored in the freeze frame data have been duplicated, one of the following factors is considered to be a possible cause of the problem:
1. The fuel level is low.
2. Improper fuel is used.
3. The spark plugs are dirty.
4. The problem is complex due to multiple factors.
After finishing repairs, check that no misfires occur in each cylinder (Cylinder #1 Misfire Count to #4).
Be sure to confirm that no misfiring cylinder DTCs are set again by conducting the confirmation driving pattern, after the repairs.
For 6 and 8 cylinder engines, the ECM intentionally does not set the specific misfiring cylinder DTCs at high engine RPM. If misfires only occur during high engine RPM driving, only DTC P0300 is set.
In the event of DTC P0300 being present, perform the following operations:
1. Clear the DTC (see DTC CHECK / CLEAR ).
2. Start the engine and conduct the confirmation driving pattern.
3. Read the misfiring rates of each cylinder or DTC (s) using the tester.
4. Repair the cylinder (s) that has a high misfiring rate or is indicated by the DTC.
5. After finishing repairs, conduct the confirmation driving pattern again, in order to verify that DTC P0300 is not set.
When either Short FT #1 or Long FT #1 in the freeze frame data is outside the range of +-20 %, the air-fuel ratio may be rich (-20 % or less) or lean (+20 % or more).
When the Coolant Temp in the freeze frame data is less than 75°C (167°F), the misfires occurred only while warming up the engine.
An extremely imbalanced drive wheel which causes body vibration may cause misfire DTCs to be detected.

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

Connect Techstream to the DLC3.
Turn the ignition switch ON.
Turn the tester ON.
Select the following menu items: Powertrain / Engine and ECT / Trouble Code.

Read DTCs.

Result

RESULT REFERENCE

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

HINT:

If any DTCs other than P0300, P030.1, P0302, P0303 and P0304 are output, troubleshoot those DTCs first.

B: GO TO DTC CHART

A: Go to Next Step

READ VALUE USING TECHSTREAM (MISFIRE RPM AND MISFIRE LOAD)
1. Connect Techstream the DLC3.
2. Turn the ignition switch to ON and turn the tester ON.
3. Select the following menu items: Powertrain / Engine and ECT / Data List / Misfire / Misfire RPM and Misfire Load,
4. Read and note the Misfire RPM and Misfire Load (engine load) values.
  HINT:
  
  The Misfire RPM and Misfire Load indicate the vehicle conditions under which the misfire occurred.
CHECK PCV HOSE CONNECTIONS
OK:

PCV hose is connected correctly and is not damaged.

NG: REPAIR OR REPLACE PCV HOSE

OK: Go to Next Step

CHECK MISFIRE COUNT

Connect Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the tester ON.
Clear DTCs (see DTC CHECK / CLEAR ).
Select the following menu items: Powertrain / Engine and ECT / Data List / Misfire / Cylinder #1 Misfire Count, #2, #3 and #4.
Allow the engine to idle.
Read each value for Cylinder #1 Misfire Count to #4 displayed on the tester. If no misfire counts occur in any cylinders, perform the following procedures:
1. Shift the gear selector lever to the D position.
2. Check the Cylinder #1 Misfire Count to #4.
3. If misfire counts are still not displayed, perform steps (h) and ( i) and then check the misfire counts again.
Drive the vehicle with the Misfire RPM and Misfire Load noted in the "READ VALUE USING TECHSTREAM (Misfire RPM AND Misfire Load)" procedures above.

Read the Cylinder #1 Misfire Count to #4 or DTCs displayed on the tester.

Result

RESULT REFERENCE

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 ECT 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: Go to step 17

A: Go to Next Step

CHECK SPARK PLUG

Remove the ignition coil and the spark plug of the misfiring cylinder.
Measure the spark plug electrode gap.
Standard gap:

1.0 to 1.1 mm (0.039 to 0.043 in.)

Fig 1: Identifying Spark Plug Electrode Gap
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the electrode for carbon deposits.

Recommended spark plug:

SPARK PLUGS REFERENCE

Manufacturers	Products
DENSO	SK20R11
NGK	IFR6A11

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

NG: REPLACE SPARK PLUG

OK: Go to Next Step

CHECK FOR SPARKS AND IGNITION
1. Disconnect the injector connectors prevent the engine from starting
  CAUTION: Always disconnect all injector connectors.
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.
NG: Go to step 29

OK: Go to Next Step
CHECK CYLINDER COMPRESSION PRESSURE OF MISFIRING CYLINDER
1. Measure the cylinder compression pressure of the misfiring cylinder.
NG: CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

OK: Go to Next Step

INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, AND/OR #40 VOLTAGE)

Disconnect the B30 ECM connector.

Fig 3: Identifying ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Turn the ignition switch ON.

Measure the voltage between the terminals of the ECM connector.

Standard voltage

VOLTAGE SPECIFICATION

Tester Connections	Specified Conditions
B13-1 - Body ground	9 to 14 V
B14-1 - Body ground	9 to 14 V
B15-1 - Body ground	9 to 14 V
B16-1 - Body ground	9 to 14 V

NG: CHECK ECM POWER SOURCE CIRCUIT

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (INJECTOR - ECM)

Disconnect the injector connector (of the misfiring cylinder).

Fig 4: Identifying Injector And ECM Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the B30 ECM connector.
Turn the ignition switch ON.

Measure the resistance between the injector and the ECM connector terminals.

Standard resistance

RESISTANCE SPECIFICATION

Cylinder	Tester Connections	Specified Conditions
No. 1	B16-2 - Ground	10 kΩ or higher
No. 1	B16-2 - B30-108 (#10)	Below 1 Ω
No. 2	B15-2- Ground	10 kΩ or higher
No. 2	B15-2-B30-107 (#20)	Below 1 Ω
No. 3	B14-2 - Ground	10 kΩ or higher
No. 3	B14-2 - B30-106 (#30)	Below 1 Ω
No. 4	B13-2 - Ground	10 kΩ or higher
No. 4	B13-2 - B30-105 (#40)	Below 1 Ω

Reconnect the injector connector.
Reconnect the ECM connector.

NG: CHECK ECM POWER SOURCE CIRCUIT

OK: Go to Next Step

CHECK FUEL INJECTOR OF MISFIRING CYLINDER
1. Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor).
NG: REPLACE FUEL INJECTOR ASSEMBLY

OK: Go to Next Step
CHECK VALVE CLEARANCE OF MISFIRING CYLINDER
NG: ADJUST VALVE CLEARANCE

OK: Go to Next Step
CHECK AIR INDUCTION SYSTEM
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
CHECK VALVE TIMING (See INSPECTION PROCEDURE )
NG: ADJUST VALVE TIMING

OK: Go to Next Step
CHECK FUEL PRESSURE
1. Check the fuel pressure (see ON-VEHICLE INSPECTION ).
NG: CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE AND FILTER

OK: Go to Next Step
READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )
NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR

OK: Go to Next Step
READ VALUE USING TECHSTREAM (MAF) (See INSPECTION PROCEDURE )
NG: REPLACE MASS AIR FLOW METER

OK: REPLACE ECM
CHECK AIR INDUCTION SYSTEM
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
CHECK VALVE TIMING
NG: ADJUST VALVE TIMING

OK: Go to Next Step
CHECK FUEL PRESSURE
1. Check the fuel pressure (see ON-VEHICLE INSPECTION ).
NG: CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE AND FILTER

OK: Go to Next Step
READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )
NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR

OK: Go to Next Step
READ VALUE USING TECHSTREAM (MAF) (See INSPECTION PROCEDURE )
NG: REPLACE MASS AIR FLOW METER

OK: Go to Next Step

REPLACE SPARK PLUG

Remove the ignition coil and the spark plug of the misfiring cylinder.
Measure the spark plug electrode gap.
Standard gap:

1.0 to 1.1 mm (0.039 to 0.043 in.)

Fig 5: Identifying Spark Plug Electrode Gap
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the electrode for carbon deposits.

Recommended spark plug:

SPARK PLUGS REFERENCE

Manufacturers	Products
DENSO	SK20R11
NGK	IFR6A11

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

NG: REPLACE SPARK PLUG

OK: Go to Next Step

CHECK SPARK AND IGNITION
1. Disconnect the injector connectors prevent the engine from starting
  CAUTION: Always disconnect all injector connectors.
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.
NG: Go to step 29

OK: Go to Next Step
CHECK CYLINDER COMPRESSION PRESSURE
1. Measure the cylinder compression pressure of the misfiring cylinder.
NG: CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (#10, #20, #30, AND/OR #40 VOLTAGE)

Disconnect the B30 ECM connector.

Fig 7: Identifying ECM Connector Terminals

Turn the ignition switch ON.

Measure the voltage between the terminals of the ECM connector.

Standard voltage

VOLTAGE SPECIFICATION

Tester Connections	Specified Conditions
B30-108 (#10) - Body ground	9 to 14 V
B30-107 (#20) - Body ground	9 to 14 V
B30-106 (#30) - Body ground	9 to 14 V
B30-105 (#40) - Body ground	9 to 14 V

NG: CHECK ECM POWER SOURCE CIRCUIT

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (INJECTOR - ECM)

Disconnect the injector connector (of the misfiring cylinder).

Fig 8: Identifying Injector And ECM Connector Terminals

Disconnect the B30 ECM connector.
Turn the ignition switch ON.

Measure the resistance between the injector and the ECM connector terminals.

Standard resistance

RESISTANCE SPECIFICATION

Cylinder	Tester Connections	Specified Conditions
No. 1	B16-2 - Ground	10 kΩ or higher
No. 1	B16-2-B30-108 (#10)	Below 1 Ω
No. 2	B15-2-Ground	10 kΩ or higher
No. 2	B15-2-B30-107 (#20)	Below 1 Ω
No. 3	B14-2- Ground	10 kΩ or higher
No. 3	B14-2 - B30-106 (#30)	Below 1 Ω
No. 4	B13-2- Ground	10 kΩ or higher
No. 4	B13-2-B30-105 (#40)	Below 1 Ω

Reconnect the injector connector.
Reconnect the ECM connector.

NG: CHECK ECM POWER SOURCE CIRCUIT

OK: Go to Next Step

CHECK FUEL INJECTOR OF MISFIRING CYLINDER
1. Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor).
NG: REPLACE FUEL INJECTOR ASSEMBLY

OK: Go to Next Step
CHECK VALVE CLEARANCE
NG: ADJUST VALVE CLEARANCE

OK: REPLACE ECM
CHANGE NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
1. Change the installed spark plug to a spark plug that functions normally.
2. Perform a spark test.
  CAUTION: 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: Go to step 30

OK: REPLACE SPARK PLUG
CHANGE TO NORMAL IGNITION COIL AND CHECK SPARK OF MISFIRING CYLINDER
NG: REPLACE ECM

OK: REPLACE IGNITION COIL ASSEMBLY