Inspection Procedure

WARNING: This page is about a different variant/trim than selected.

HINT:

If any DTCs other than misfire DTCs are output, troubleshoot those DTCs first.
Read freeze frame data using the Techstream. 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 +/-20%, the air fuel ratio may be rich (-20% or less) or lean (+20% or more).
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 ANY OTHER DTCS OUTPUT (IN ADDITION TO MISFIRE DTCS)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain/Engine/Trouble Codes.

Read the DTCs.

HINT:

Write down the output DTCs.

Result

RESULT CHART

Result	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, P0301, 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 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/Misfire/Misfire RPM and Misfire Load.
5. 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.
CHECK PCV HOSE CONNECTIONS
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

READ VALUE USING TECHSTREAM (CATALYST OT MF F/C)

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain/Engine/Data List/All Data/Catalyst OT MF F/C.

Read the value displayed on the Techstream.

Result

RESULT CHART

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

B: Go to step 6

A: Go to next step

PERFORM ACTIVE TEST USING TECHSTREAM (PROHIBIT CAT OT F/C)
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/Active Test/Prohibit the Catalyst OT Misfire prevent F/C.
5. 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.

READ VALUE USING TECHSTREAM (CYLINDER MISFIRE COUNT)

Enter the following menus: Powertrain/Engine/Data List/All Data/Misfire/Cylinder #1 Misfire Count, Cylinder #2 Misfire Count, Cylinder #3 Misfire Count and Cylinder #4 Misfire Count.
Start the engine and allow the engine to idle.
Read each value for Cylinder #1 Misfire Count to Cylinder #4 Misfire Count displayed on the Techstream. If no misfire counts occur in any cylinders, perform steps (d) and (e) 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 Cylinder #4 Misfire Count or DTCs displayed on the Techstream.

Result

RESULT CHART

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 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: Go to step 18

A: Go to next step

INSPECT SPARK PLUG

Remove the ignition coil and the spark plug from the misfiring cylinder.

Measure the spark plug electrode gap.

Standard gap:

1.0 to 1.1 mm (0.0394 to 0.0433 in.)

NOTE: If the electrode gap is more than 1.1 mm (0.0433 in.), replace the spark plug. Do not adjust the electrode gap.

Recommended Spark Plug

MANUFACTURER CHART

Manufacturer	Product
DENSO made	SK16HR11

Fig 1: Identifying Spark Plug Electrode Gap

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the electrode for carbon deposits.
NOTE: If necessary, clean the spark plug.
Reinstall the ignition coil and spark plug.
NG: REPLACE SPARK PLUG (See REMOVAL )

OK: Go to next step

CHECK FOR SPARK (SPARK TEST)
1. Disconnect the injector connectors to prevent the engine from starting.
  CAUTION: Always disconnect all the 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 for spark.
  NOTE: Do not crank the engine for more than 2 seconds.
  
  Fig 2: Checking Spark Plug Spark
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  OK:
  
  Spark jumps across electrode gap.
6. Install the ignition coil.
7. Reconnect the injector connectors.
  NG: Go to step 29
  
  OK: Go to next step
CHECK CYLINDER COMPRESSION PRESSURE
1. Measure the cylinder compression pressure of the misfiring cylinder (See ON-VEHICLE INSPECTION ).
  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 ECM connector.
Turn the ignition switch to ON.

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

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
B48-7 (#10) - Body ground	Ignition switch ON	11 to 14 V
B48-8 (#20) - Body ground	Ignition switch ON	11 to 14 V
B48-9 (#30) - Body ground	Ignition switch ON	11 to 14 V
B48-10 (#40) - Body ground	Ignition switch ON	11 to 14 V

Reconnect the ECM connector.

Fig 3: Disconnecting B48 ECM Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: GO TO FUEL INJECTOR 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) (See INSPECTION ).
  NG: REPLACE FUEL INJECTOR (See REMOVAL )
  
  OK: Go to next step
CHECK INTAKE SYSTEM
1. Check the intake system for vacuum leakage (See ON-VEHICLE INSPECTION ).
  OK:
  
  No leakage from intake system.
  
  NG: REPAIR OR REPLACE INTAKE SYSTEM
  
  OK: Go to next step
CHECK INTAKE AIR CONTROL VALVE (FOR TUMBLE CONTROL VALVE)
1. Check the intake air control valve for tumble control valve (See ON-VEHICLE INSPECTION ).
  NG: REPLACE INTAKE AIR CONTROL VALVE (FOR TUMBLE CONTROL VALVE) (See INTAKE AIR CONTROL VALVE ACTUATOR (FOR TCV) )
  
  OK: Go to next step
CHECK VALVE TIMING (See INSPECTION PROCEDURE )
NG: ADJUST VALVE TIMING (See REMOVAL )

OK: Go to next step
CHECK FUEL PRESSURE
1. Check the fuel pressure (See ON-VEHICLE INSPECTION ).
  NG: REPAIR OR REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE OR FILTER
  
  OK: Go to next step
READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )
NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK: Go to next step
INSPECT MASS AIR FLOW METER (See INSPECTION PROCEDURE )
NG: REPLACE MASS AIR FLOW METER (See REMOVAL )

OK: REPLACE ECM (See REMOVAL )
CHECK INTAKE SYSTEM
1. Check the intake system for vacuum leakage (See ON-VEHICLE INSPECTION ).
  OK:
  
  No leakage from intake system.
  
  NG: REPAIR OR REPLACE INTAKE SYSTEM
  
  OK: Go to next step
CHECK INTAKE AIR CONTROL VALVE (FOR TUMBLE CONTROL VALVE)
1. Check the intake air control valve for tumble control valve (See ON-VEHICLE INSPECTION ).
  NG: REPLACE INTAKE AIR CONTROL VALVE (FOR TUMBLE CONTROL VALVE) (See INTAKE AIR CONTROL VALVE ACTUATOR (FOR TCV) )
  
  OK: Go to next step
CHECK VALVE TIMING (See INSPECTION PROCEDURE )
NG: ADJUST VALVE TIMING (See REMOVAL )

OK: Go to next step
CHECK FUEL PRESSURE
1. Check the fuel pressure (See ON-VEHICLE INSPECTION ).
  NG: REPAIR OR REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE OR FILTER
  
  OK: Go to next step
READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )
NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK: Go to next step
INSPECT MASS AIR FLOW METER (See INSPECTION PROCEDURE )
NG: REPLACE MASS AIR FLOW METER (See REMOVAL )

OK: Go to next step

INSPECT SPARK PLUG

Remove the ignition coil and the spark plug from the misfiring cylinder.

Measure the spark plug electrode gap.

Standard gap:

1.0 to 1.1 mm (0.0394 to 0.0433 in.)

NOTE: If the electrode gap is more than 1.1 mm (0.0433 in.), replace the spark plug. Do not adjust the electrode gap.

Recommended Spark Plug

MANUFACTURER CHART

Manufacturer	Product
DENSO made	SK16HR11

Fig 4: Identifying Spark Plug Electrode Gap

Check the electrode for carbon deposits.
NOTE: If necessary, clean the spark plug.
Reinstall the ignition coil and spark plug.
NG: REPLACE SPARK PLUG (See REMOVAL )

OK: Go to next step

CHECK FOR SPARK (SPARK TEST)
1. Disconnect the injector connectors to prevent the engine from starting.
  CAUTION: Always disconnect all the 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 for spark.
  NOTE: Do not crank the engine for more than 2 seconds.
  
  OK:
  
  Spark jumps across electrode gap.
6. Install the ignition coil.
7. Reconnect the injector connectors.
  NG: Go to step 29
  
  Fig 5: Checking Spark Plug Spark
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  OK: Go to next step
CHECK CYLINDER COMPRESSION PRESSURE
1. Measure the cylinder compression pressure of the misfiring cylinder (See ON-VEHICLE INSPECTION ).
  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 ECM connector.
Turn the ignition switch to ON.

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

Standard Voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
B48-7 (#10) - Body ground	Ignition switch ON	11 to 14 V
B48-8 (#20) - Body ground	Ignition switch ON	11 to 14 V
B48-9 (#30) - Body ground	Ignition switch ON	11 to 14 V
B48-10 (#40) - Body ground	Ignition switch ON	11 to 14 V

Reconnect the ECM connector.
NG: GO TO FUEL INJECTOR CIRCUIT

Fig 6: Disconnecting B48 ECM Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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) (See INSPECTION ).
  NG: REPLACE FUEL INJECTOR (See REMOVAL )
  
  OK: REPLACE ECM (See REMOVAL )
CHANGE TO KNOWN GOOD SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
1. Change the installed spark plug to a known good spark plug.
2. Perform a spark test.
  CAUTION: Always disconnect all the 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 connectors.
  3. Touch the spark plug to the cylinder head bolts.
  4. Check if spark occur while the engine is being cranked.
    OK:
    
    Spark jumps across electrode gap.
    
    NG: Go to step 30
    
    OK: REPLACE SPARK PLUG (See REMOVAL )
CHANGE TO KNOWN GOOD IGNITION COIL AND CHECK SPARK OF MISFIRING CYLINDER
1. Change the known good ignition coil.
2. Perform a spark test.
  CAUTION: Always disconnect all the 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 connectors.
  3. Touch the spark plug to the cylinder head bolts.
  4. Check if spark occurs while the engine is being cranked.
    OK:
    
    Spark jumps across electrode gap.
    
    NG: REPLACE ECM (See REMOVAL )
    
    OK: REPLACE IGNITION COIL (See REMOVAL )