Part 2

2UR-GSE ENGINE CONTROL: SFI SYSTEM: P0300: Random / Multiple Cylinder Misfire Detected

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

DTC P0307 - Cylinder 7 Misfire Detected

DTC P0308 - Cylinder 8 Misfire Detected

(Continued)

INSPECTION PROCEDURE
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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
- 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 is 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 #8 Misfire Count).
- Be sure to confirm that no misfiring cylinder DTCs are set again by conducting the confirmation driving pattern after finishing repairs.
- For 8 cylinder engine, the ECM intentionally does not set the specific misfiring cylinder DTCs at high engine speed. If misfires occur only in high engine speed areas, only DTC P0300 is set.
In the event of DTC P0300 being present, perform the following operations:
1 Clear DTCs DTC Check / Clear.
2 Start the engine and conduct the confirmation driving pattern.
3 Read the misfire count of each cylinder or DTC(s) using the Techstream.
4 Repair the cylinder(s) that has a high misfiring count 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 one of Short FT #1, Long FT #1, Short FT #2 or Long FT #2 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 misfire have occurred only while warming up the engine.
- An extremely unbalanced drive wheel which causes body vibration may cause misfire DTCs to be detected.

PROCEDURE

1. CHECK ANY OTHER DTC OUTPUT (IN ADDITION TO MISFIRE DTCS)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Result:

HINT: If any DTCs other than P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 and P0308 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (MISFIRE RPM AND MISFIRE LOAD)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Engine / Data List / Misfire / Misfire RPM and Misfire Load.
(d) 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 -- Continue to next step.

3. CHECK PCV HOSE (HOSE CONNECTIONS)
OK:
PCV hose is connected correctly and is not damaged.
NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.

4. CHECK MISFIRE COUNT OF PORT INJECTION
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Clear DTCs DTC Check / Clear.
(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Port. (Procedure "A")
(f) Allow the engine to idle.
(g) Monitor all of the misfire count values that are displayed on the Techstream: Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire Count to Cylinder #8 Misfire Count.
If no misfire counts occur for any of the cylinders, perform the following procedure: (Procedure "B")
(1) Move the shift lever to D.
(2) Repeat procedure "A" to "B" above.
(3) Monitor all of the misfire count values that are displayed on the tester.
Result:

B -- CHECK MISFIRE COUNT
A -- Continue to next step.

5. CHECK MISFIRE COUNT OF DIRECT INJECTION
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Clear DTCs DTC Check / Clear.
(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct. (Procedure "A")
(f) Allow the engine to idle.
(g) Monitor all of the misfire count values that are displayed on the Techstream.
(1)Enter the following menus: Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire Count Cylinder #8 Misfire Count.
If no misfire counts occur for any of the cylinders, perform the following procedure: (Procedure "B")
(1) Move the shift lever to D.
(2) Repeat procedure "A" to "B" above.
(3) Monitor all of the misfire count values that are displayed on the Techstream.
Result:

C -- CHECK MISFIRE COUNT
B -- CHECK FUEL PRESSURE SENSOR
A -- REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION)
6. CHECK MISFIRE COUNT
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Clear DTCs DTC Check / Clear.
(e) Enter the following menus: Powertrain / Engine / Data List / Misfire RPM, Misfire Load, Cylinder #1 Misfire Count to Cylinder #8 Misfire Count and Injection Way.
(f) Drive the vehicle with Misfire RPM and Misfire Load.
(g) Monitor all of the misfire count values or DTCs and Injection Way displayed on the Techstream.
Result:

E -- CHECK FUEL PRESSURE SENSOR
D -- REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION MALFUNCTIONING CYLINDER)
C -- CHECK INTAKE SYSTEM
B -- CHECK SPARK PLUG
A -- CHECK FOR INTERMITTENT PROBLEMS
7. CHECK MISFIRE COUNT
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Clear DTCs DTC Check / Clear.
(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct. (Procedure "A")
(f) Allow the engine to idle.
(g) Monitor all of the misfire count values that are displayed on the Techstream: Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire Count to Cylinder #8 Misfire Count.
If no misfire counts occur for any of the cylinders, perform the following procedure: (Procedure "B")
(1) Move the shift lever to D.
(2) Repeat procedure "A" to "B" above.
(3) Monitor all of the misfire count values that are displayed on the Techstream.
Result:

D -- CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
C -- REPLACE INJECTOR ASSEMBLY (MALFUNCTIONING CYLINDER)
B -- CHECK INTAKE SYSTEM
A -- Continue to next step.

8. CHECK SPARK PLUG

(a) Remove the ignition coil and the spark plug of the misfiring cylinder.
(b) Measure the spark plug electrode gap.
Standard gap:
1.0 to 1.4 mm (0.039 to 0.055 in.)
(c) Check the electrode for carbon deposits.

Recommended Spark Plug

NOTE:
If the electrode gap is larger than 1.4 mm (0.055 in.), replace the spark plug. Do not adjust the electrode gap.
(d) Reinstall the ignition coil and spark plug.
NG -- REPLACE SPARK PLUG
OK -- Continue to next step.

9. CHECK FOR SPARK AND IGNITION
(a) Remove the ignition coil assemblies.
(b) Remove the spark plugs.
(c) Install the spark plug to the ignition coil.
(d) Disconnect the 2 fuel delivery pipe connectors.

(e) Disconnect the 4 connectors with wire harness locks from the 2 injector drivers.
(f) Attach the spark plug assembly to the cylinder head cover.

(a) Remove the cylinder head cover bank 1 and bank 2.
(b) Turn the crankshaft pulley, and align its groove with the timing mark "0" of the timing chain cover.
(c) Check that the timing marks of the camshaft timing gears and camshaft timing exhaust gears are at the positions shown in the illustration.
OK:
Timing marks on camshaft timing gears are aligned as shown in the illustration.
(d) Reinstall the cylinder head covers.
NG -- ADJUST VALVE TIMING
OK -- Continue to next step.

14. CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
(a) Check the fuel pressure (low pressure side) Testing and Inspection.
NG -- CHECK FUEL PUMP OPERATION
OK -- Continue to next step.

15. READ VALUE USING TECHSTREAM (COOLANT TEMP)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.
(e) Read the Data List twice, when the engine is both cold and warmed up.
Standard:
With cold engine
Same as ambient air temperature.
With warm engine
Between 75°C and 95°C (167°F and 203°F).
NG -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR
OK -- Continue to next step.

16. INSPECT MASS AIR FLOW METER SUB-ASSEMBLY
(a) Inspect the mass air flow meter sub-assembly On-Vehicle Inspection.
NG -- REPLACE MASS AIR FLOW METER SUB-ASSEMBLY
OK -- REPLACE ECM
17. CHECK INTAKE SYSTEM
(a) Check the intake system for vacuum leaks Testing and Inspection.
OK:
No leaks in the intake system.
NG -- REPAIR OR REPLACE INTAKE SYSTEM
OK -- Continue to next step.

18. CHECK VALVE TIMING

(a) Remove the cylinder head cover bank 1 and bank 2.
(b) Turn the crankshaft pulley, and align its groove with the timing mark "0" of the timing chain cover.
(c) Check that the timing marks of the camshaft timing gears and camshaft timing exhaust gears are at the positions shown in the illustration.
OK:
Timing marks on camshaft timing gears are aligned as shown in the illustration.
(d) Reinstall the cylinder head covers.
NG -- ADJUST VALVE TIMING
OK -- Continue to next step.

19. CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
(a) Check the fuel pressure (low pressure side) Testing and Inspection.
NG -- CHECK FUEL PUMP OPERATION
OK -- Continue to next step.

20. READ VALUE USING TECHSTREAM (COOLANT TEMP)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream ON.
(d) Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.
(e) Read the Data List twice when the engine is both cold and warmed up.
Standard:
With cold engine
Same as ambient air temperature.
With warm engine
Between 75°C and 95°C (167°F and 203°F).
NG -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR
OK -- Continue to next step.

21. INSPECT MASS AIR FLOW METER SUB-ASSEMBLY
(a) Inspect the mass air flow meter sub-assembly On-Vehicle Inspection.
NG -- REPLACE MASS AIR FLOW METER SUB-ASSEMBLY
OK -- Continue to next step.

22. CHECK SPARK PLUG

NOTE:
If the electrode gap is larger than 1.4 mm (0.055 in.), replace the spark plug. Do not adjust the electrode gap.
(d) Reinstall the ignition coil and spark plug.
NG -- REPLACE SPARK PLUG
OK -- Continue to next step.

23. CHECK FOR SPARK AND IGNITION
(a) Remove the ignition coil assemblies.
(b) Remove the spark plugs.
(c) Install the spark plug to the ignition coil.
(d) Disconnect the 2 fuel delivery pipe connectors.

(e) Disconnect the 4 connectors with wire harness locks from the 2 injector drivers.
(f) Attach the spark plug assembly to the cylinder head cover.

(g) Crank the engine for less than 2 seconds and check the spark.
OK:
Sparks jump across the electrode gap.
(h) Reconnect the 4 connectors with wire harness locks to the 2 injector drivers.
(i) Reconnect the 2 fuel delivery pipe connectors.
(j) Reinstall the spark plugs.
(k) Reinstall the ignition coil assemblies.
NG -- CHANGE TO NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
OK -- Continue to next step.

24. CHECK CYLINDER COMPRESSION PRESSURE (MALFUNCTIONING CYLINDER)
(a) Measure the cylinder compression pressure of the misfiring cylinder Engine.
NG -- CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION
OK -- Continue to next step.

25. CHECK VALVE CLEARANCE (MISFIRING CYLINDER)
(a) Check the valve clearance Adjustments.
NG -- ADJUST VALVE CLEARANCE
OK -- REPLACE ECM
26. CHECK FUEL PRESSURE (LOW PRESSURE SIDE)
(a) Check the fuel pressure (low pressure side) Testing and Inspection.
NG -- CHECK FUEL PUMP OPERATION
OK -- REPLACE FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION)
27. CHECK FUEL PRESSURE SENSOR
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
(e) While revving the engine, check that the fuel pressure fluctuates.
Standard:
Idling
3.5 to 4.5 MPa
2000 rpm (No load)
7 to 9 MPa
HINT: The A/C switch and all accessory switches should be OFF, and the shift lever should be in N or P, and the engine should be fully warmed up.

NG -- CHECK MISFIRE COUNT
OK -- Continue to next step.

28. READ VALUE USING TECHSTREAM
(a) Connect the Techstream to the DLC3.
(b) Start the engine and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection way / Direct.
HINT: The A/C switch and all accessory switches should be OFF, and the shift lever should be in N or P, and the engine should be fully warmed up.
(d) Read the value.
(1) Enter the following menus: Data List / A/F Control System / Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4).
Result:

D -- REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION MALFUNCTIONING CYLINDER)
C -- REPLACE ECM
B -- REPLACE FUEL PRESSURE SENSOR
A -- REPLACE FUEL PRESSURE SENSOR
29. CHANGE TO NORMAL SPARK PLUG AND CHECK SPARK OF MISFIRING CYLINDER
(a) Change the installed spark plug to a spark plug that functions normally.
(b) Perform a spark test.
CAUTION:
Always disconnect each injector connector.
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 2 fuel delivery pipe connectors.

(3) Disconnect the 4 connectors with wire harness locks from the 2 injector drivers.
(4) Ground the spark plug.
(5) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across the electrode gap.
NG -- CHANGE TO NORMAL IGNITION COIL AND SPARK OF MISFIRING CYLINDER
OK -- REPLACE SPARK PLUG
30. CHANGE TO NORMAL IGNITION COIL AND SPARK OF MISFIRING CYLINDER
(a) Change the installed ignition coil to a ignition coil that functions normally.
(b) Perform a spark test.
CAUTION:
Always disconnect each injector connector.
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 2 fuel delivery pipe connectors.

(3) Disconnect the 4 connectors with wire harness locks from the 2 injector drivers.
(4) Ground the spark plug.
(5) Check if sparks occur while the engine is being cranked.
OK:
Sparks jump across the electrode gap.
NG -- REPLACE ECM
OK -- REPLACE IGNITION COIL ASSEMBLY
31. CHECK FUEL PUMP OPERATION
(a) Check the fuel pump operation Testing and Inspection.
NG -- REPAIR OR REPLACE FUEL PUMP CONTROL CIRCUIT
OK -- Continue to next step.

32. CHECK FUEL LINE
(a) Check the fuel line for leakage and blockage.
NG -- REPAIR OR REPLACE FUEL LINE
OK -- CHECK AND REPLACE FUEL SYSTEM (FUEL PUMP REGULATOR, FUEL FILTER)
33. CHECK MISFIRE COUNT
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.
(e) Allow the engine to idle.
(f) Monitor all of the misfire count values that are displayed on the Techstream: Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire Count to Cylinder #8 Misfire Count.
If no misfire counts occur for any of the cylinders, perform the following procedure:
(1) Move the shift lever to D.
(2) Monitor all of the misfire count values that are displayed on the Techstream.
Result:

B -- REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION)
A -- Continue to next step.

34. INSPECT INJECTOR DRIVER
(a) Turn the engine switch off.
(b) Replace the No. 1 and No. 2 injector drivers with normal ones from another vehicle.
NOTE:
Do not disconnect and reconnect the connectors with the engine switch on (IG), as the injector driver (EDU) may be damaged.
(c) Connect the Techstream to the DLC3.
(d) Start the engine.
(e) Clear DTCs DTC Check / Clear.
(f) Perform the driving test.
(g) Enter the following menus: Powertrain / Engine / Trouble Codes.
(h) Read the DTCs.

Result

B -- REPLACE INJECTOR DRIVER (NO. 1 AND NO. 2)
A -- Continue to next step.

35. INSPECT FUEL RELIEF VALVE ASSEMBLY
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
(e) Record the Fuel Press value.
(f) Turn the engine switch off.
(g) Wait for 10 seconds.
(h) Turn the engine switch on (IG) and turn the Techstream ON.
(i) Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
(j) Compare the Fuel Press value recorded with the engine running to the Fuel Press value currently shown on the Techstream.
Result:

B -- REPLACE FUEL RELIEF VALVE ASSEMBLY
A -- REPLACE FUEL PUMP ASSEMBLY (HIGH PRESSURE)