DTC P0301, P0302, P0303, P0304, P0305, P0306 [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513)

BME010200300202

European (L.H.D.) Specs.

DTC P0301

DTC P0302

DTC P0303

DTC P0304

DTC P0305

DTC P0306

Cylinder No.1 misfire detection

Cylinder No.4 misfire detection

Cylinder No.2 misfire detection

Cylinder No.5 misfire detection

Cylinder No.3 misfire detection

Cylinder No.6 misfire detection

DETECTION CONDITION

• PCM monitors crankshaft position sensor input signal interval time. PCM calculates the change of the interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, PCM detects a misfire in the corresponding cylinder. While the engine is running, PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions and calculates misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.
Diagnostic support note
• This is a continuous monitor (MISFIRE).
• MIL illuminates if PCM detects the misfire which affects emission performance in two consecutive drive cycles.
• PENDING CODE is available if PCM detects the misfire which affects emission performance during first drive cycle.
• MIL flashes if PCM detects the misfire which can damage the catalytic converter during first drive cycle. Therefore, PENDING CODE is not available while MIL flashes.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Spark plug malfunction
• Fuel injector malfunction
• Air suction in intake air system (between dynamic chamber and cylinder head)
• Inadequate engine compression due to engine internal malfunction
• Related connector or terminal malfunction
• Related wiring harness malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record FREEZE FRAME DATA on repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
• Check for related Service Information availability.
• Is any related Service Information available?
Yes
Perform repair or diagnosis according to available Service Information.
• If vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY RELATED PENDING CODE OR STORED DTCS
• Turn the ignition switch off, then to the ON position (Engine off).
• Verify related pending code or stored DTCs.
• Is other DTCs present?
Yes
Go to the applicable DTC inspection.
No
Go to the next step.
4
VERIFY CURRENT INPUT SIGNAL STATUS (KEY TO ON /IDLE)
• Access ECT, IAT, MAF, RPM, TP and VSS PIDs using WDS or equivalent.
• Is there any signal that is far out of specification when the ignition switch is at the ON position and the engine runs at idle?
Yes
Inspect the circuit and/or part according to inspection results. Then go to Step 12.
No
Go to the next step.
5
VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION
• Inspect PID while simulating FREEZE FRAME DATA condition.
• Is there any signal which causes drastic changes?
Yes
Inspect the circuit and/or part according to inspection results. Then go to Step 12.
No
Go to the next step.
6
INSPECT SPARK PLUG CONDITION
• Turn the ignition switch off.
• Remove spark plug from suspected cylinder.
• Inspect spark plug condition:
- Cracks
- Excess wear
- Gap
- Wet
• Is any problem found on spark plug?
Yes
• If the spark plug is wet, fuel flooding is suspected. Go to step 8.
• If spark plug has a cracks, excess wear or improper gap, replace the malfunctioning spark plug. Then go to Step 12.
No
Go to the next step.
7
INSPECT FUEL INJECTOR HARNESS
• Remove intake air system parts.
• Disconnect fuel injector connector on suspected cylinder.
• Connect NOID LIGHT to fuel injector connector terminals.
• Check dim of light during cranking?
Yes
Go to the next step.
No
Inspect for fuel injector wiring harnesses.
Repair or replace it if necessary, then go to Step 12.
8
INSPECT FUEL INJECTOR OPERATION
• Remove fuel injector from suspected cylinder.
• Swap the fuel injector with the fuel injector on other cylinder.
• Start the engine and run it at idle.
• Is misfire DTC for cylinder which has a malfunctioning fuel injector?
Yes
Replace the fuel injector, then go to step 12.
No
Go to the next step.
9
INSPECT FOR AIR SUCTION AT INTAKE AIR SYSTEM
• Inspect for air leakage at the following:
- Around connection of dynamic chamber and intake manifold
- Around connection of intake manifold and cylinder head
• Is air leakage found?
Yes
Repair or replace the part, then go to Step 12.
No
Go to the next step.
10
INSPECT SEALING OF ENGINE COOLANT PASSAGE
Warning
• Removing radiator cap when radiator is hot is dangerous, Scalding coolant and steam may shoot out and cause serious injury.
• When removing radiator cap, wrap thick cloth around and turn it slowly.
• Remove radiator cap.
• Implement procedure to bleed air from engine coolant, then run engine at idle.
• Is there any small bubble which makes engine coolant white at filling opening?
Note
• Large bubbles are normal since they are remaining air coming out from engine coolant passage.
Yes
Air gets in from poor sealing on head gasket or other areas between combustion chamber and engine coolant passage. Repair or replace faulty parts, then go to Step 12.
No
Go to the next step.
11
INSPECT ENGINE COMPRESSION
• Inspect engine compression.
• Is engine compression normal?
Yes
Go to the next step.
No
Overhaul the engine, then go to the next step.
12
VERIFY TROUBLESHOOTING OF MISFIRE DTC COMPLETED
• Make sure to reconnect all disconnected connectors.
• Start the engine.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Run PCM adaptive memory procedure drive mode.
• Is the same PENDING CODE or stored code of same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
13
VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
• Is there any DTC present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.