Toyota Tundra. Manual — part 1191

11. INSPECT ECM TERMINAL OF MISFIRING CYLINDER (#10, #20, #30, #40, #50 AND/OR #60

VOLTAGE)

a. Disconnect the D74 ECM connector.

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

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - ECM)

Fig. 108: Identifying D74 ECM Connector Terminals

OK : Go to next step

12. CHECK FUEL INJECTOR OF MISFIRING CYLINDER

a. Check the injector injection (whether fuel volume is high or low, and whether injection pattern is

poor). (See INSPECTION ).

NG : REPLACE FUEL INJECTOR ASSEMBLY . (See FUEL INJECTOR ).

OK : Go to next step

Tester Connection

Switch Condition Specified Condition

D74-86 (#10) - D74-43 (E01) Ignition switch ON

11 to 14 V

D74-109 (#20) - D74-43 (E01) Ignition switch ON

11 to 14 V

D74-85 (#30) - D74-43 (E01) Ignition switch ON

11 to 14 V

D74-108 (#40) - D 74-43 (E01) Ignition switch ON

11 to 14 V

D74-84 (#50) - D74-43 (E01) Ignition switch ON

11 to 14 V

D74-107 (#60) - D74-43 (E01) Ignition switch ON

11 to 14 V

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

13. CHECK VALVE CLEARANCE OF MISFIRING CYLINDER

a. Check the valve clearance (See ADJUSTMENT ).

NG : ADJUST VALVE CLEARANCE (See ADJUSTMENT )

OK : Go to next step

14. CHECK AIR INDUCTION SYSTEM

a. Check the air induction system for vacuum leakage. (See ON-VEHICLE INSPECTION ).

OK: No leakage from air induction system.

NG : REPAIR OR REPLACE AIR INDUCTION SYSTEM

OK : Go to next step

15. CHECK VALVE TIMING (See INSPECTION PROCEDURE )

NG : ADJUST VALVE TIMING

OK : Go to next step

16. CHECK FUEL PRESSURE

a. 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

17. READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )

NG : REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK : Go to next step

18. INSPECT MASS AIR FLOW METER

a. Inspection mass air flow meter (See REMOVAL ).

NG : REPLACE MASS AIR FLOW METER (See REMOVAL )

OK : REPLACE ECM (See REMOVAL )

19. CHECK AIR INDUCTION SYSTEM

a. Check the air induction system for vacuum leakage. (See ON-VEHICLE INSPECTION ).

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

OK: No leakage from air induction system.

NG : REPAIR OR REPLACE AIR INDUCTION SYSTEM

OK : Go to next step

20. CHECK VALVE TIMING (See INSPECTION PROCEDURE )

NG : ADJUST VALVE TIMING

OK : Go to next step

21. CHECK FUEL PRESSURE

a. 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

22. READ VALUE USING TECHSTREAM (COOLANT TEMP) (See INSPECTION PROCEDURE )

NG : REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK : Go to next step

23. INSPECT MASS AIR FLOW METER

a. Inspection mass air flow meter (See REMOVAL ).

NG : REPLACE MASS AIR FLOW METER (See REMOVAL )

OK : Go to next step

24. CHECK SPARK PLUG

a. Remove the ignition coil and the spark plug of the misfiring cylinder.

b. Measure the spark plug electrode gap.

Maximum gap:

1.3 mm (0.0512 in.)

c. Check the electrode for carbon deposits.

Recommended spark plug:

SPARK PLUG SPECIFICATION

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

NG : REPLACE SPARK PLUG . (See IGNITION COIL AND SPARK PLUG ).

Fig. 109: Checking Spark Plug Electrode Gap

OK : Go to next step

25. CHECK FOR SPARKS AND IGNITION

a. Disconnect the injector connectors to prevent the engine from starting.

b. Remove the ignition coil from the cylinder head.

c. Install the spark plug onto the ignition coil.

d. Attach the spark plug assembly to the cylinder head.

e. Crank the engine for less than 2 seconds and check the spark.

OK: Sparks jump across electrode gap.

f. Install the ignition coil.

g. Reconnect the injector connectors.

NG : Go to step 31

OK : Go to next step

26. CHECK CYLINDER COMPRESSION PRESSURE

a. Measure the cylinder compression pressure of the misfiring cylinder (See ON-VEHICLE

Manufacturer Product

DENSO

FK20HR11

NOTE:

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

CAUTION: Always disconnect all injector connectors.

NOTE:

Do not crank the engine for more than 2 seconds.

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra