DTC P0301:00, P0302:00, P0303:00, P0304:00 [L3 Turbo]

DTC P0301:00	Cylinder No.1 misfire detected
DETECTION CONDITION	• The PCM monitors the CKP sensor input signal interval time. The PCM calculates the change of interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding cylinder. While the engine is running, the PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions and calculates a misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, the 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). • The MIL illuminates if the PCM detects a misfire which affects emission performance in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. • The MIL flashes if the PCM detects a misfire which can damage the catalytic converter during the first drive cycle. • PENDING CODE is available if the PCM detects a misfire which affects emission performance during first drive cycle. • FREEZE FRAME DATA (Mode 2)/Snapshot data is available. • DTCs are stored in the PCM memory.
POSSIBLE CAUSE	• Erratic signal to PCM ― APP sensor signal malfunction ― ECT sensor signal malfunction ― IAT sensor signal malfunction ― MAF sensor signal malfunction ― CKP sensor signal malfunction ― TP sensor signal malfunction ― VSS signal malfunction ― Related connector or terminals malfunction ― Related wiring harness malfunction • Air suction in intake air system (between dynamic chamber and cylinder head) • Leakage engine coolant to combustion chamber • Fuel injector related wiring harness malfunction • Ignition system malfunction ― Spark plug malfunction ― Ignition coil malfunction ― Ignition coil related wiring harness malfunction • Inadequate engine compression due to engine internal malfunction • Fuel injector malfunction • PCM malfunction

DTC P0301:00

Cylinder No.1 misfire detected

DTC P0302:00

Cylinder No.2 misfire detected

DTC P0303:00

Cylinder No.3 misfire detected

DTC P0304:00

Cylinder No.4 misfire detected

DETECTION CONDITION

• The PCM monitors the CKP sensor input signal interval time. The PCM calculates the change of interval time for each cylinder. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding cylinder. While the engine is running, the PCM counts the number of misfires that occurred at 200 crankshaft revolutions and 1,000 crankshaft revolutions and calculates a misfire ratio for each crankshaft revolution. If the ratio exceeds the preprogrammed criteria, the 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).

• The MIL illuminates if the PCM detects a misfire which affects emission performance in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.

• The MIL flashes if the PCM detects a misfire which can damage the catalytic converter during the first drive cycle.

• PENDING CODE is available if the PCM detects a misfire which affects emission performance during first drive cycle.

• FREEZE FRAME DATA (Mode 2)/Snapshot data is available.

• DTCs are stored in the PCM memory.

POSSIBLE CAUSE

• Erratic signal to PCM

― APP sensor signal malfunction

― ECT sensor signal malfunction

― IAT sensor signal malfunction

― MAF sensor signal malfunction

― CKP sensor signal malfunction

― TP sensor signal malfunction

― VSS signal malfunction

― Related connector or terminals malfunction

― Related wiring harness malfunction

• Air suction in intake air system (between dynamic chamber and cylinder head)

• Leakage engine coolant to combustion chamber

• Fuel injector related wiring harness malfunction

• Ignition system malfunction

― Spark plug malfunction

― Ignition coil malfunction

― Ignition coil related wiring harness malfunction

• Inadequate engine compression due to engine internal malfunction

• Fuel injector malfunction

• PCM malfunction

STEP	INSPECTION	ACTION
1	VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED • Have the snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (misfire related) been recorded?	Yes	Go to the next step.
No	Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to the next step.
2	VERIFY RELATED SERVICE INFORMATION AVAILABILITY • Verify related Service Information availability. • Is any related Service Information available?	Yes	Perform repair or diagnosis according to the available Service Information. • If the vehicle is not repaired, go to the next step.
No	Go to the next step.
3	VERIFY RELATED PENDING CODE AND STORED DTC • Turn the ignition switch off, then to the ON position (engine off). • Perform the DTC Reading Procedure and Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Are any other DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No	Go to the next step.
4	VERIFY CURRENT INPUT SIGNAL STATUS (KEY TO ON/IDLE) • Access the following PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) ― APP1 ― APP2 ― ECT ― IAT ― MAF ― RPM ― TP REL ― VSS • Is there any signal that is far out of specification when the ignition switch is turned to the ON position and the engine idles? (See PCM INSPECTION [L3 Turbo].)	Yes	Inspect the suspected circuit. • If the inspection results are normal: ― Go to the next step. • If the inspection results are not normal: ― Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
No	Go to the next step.
5	VERIFY CURRENT INPUT SIGNAL STATUS UNDER FREEZE FRAME DATA (MODE 2) CONDITION • Access the same PIDs as in Step 4 while simulating the FREEZE FRAME DATA (Mode 2) condition. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Is there any signal which causes drastic changes?	Yes	Inspect the suspected circuit. • If the inspection results are normal: ― Go to the next step. • If the inspection results are not normal: ― Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
No	Go to the next step.
6	INSPECT INTAKE-AIR SYSTEM FOR AIR SUCTION • Inspect for air leakage at the following: ― Around connection of dynamic chamber and intake manifold ― Around connection of intake manifold and cylinder head Note • Engine speed may change when rust penetrating agent is sprayed on the air suction area. • Is air leakage found?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
No	Go to the next step.
7	INSPECT SEALING OF ENGINE COOLANT PASSAGE • Perform the “ENGINE COOLANT LEAKAGE INSPECTION”. (See ENGINE COOLANT LEAKAGE INSPECTION [L3 Turbo].) • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
No	Go to the next step.
8	INSPECT FUEL INJECTOR WIRING HARNESS • Remove the intake air system parts. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].) • Disconnect the fuel injector connector on suspected cylinder. • Connect the NOID LIGHT to the fuel injector terminals. • Inspect dim of light during cranking. • Does the light illuminate?	Yes	Go to the next step.
No	Inspect the fuel injector wiring harnesses. • Repair or replace the suspected wiring harness, if necessary. Go to Step 14.
9	INSPECT WHETHER MALFUNCTION IS IN IGNITION SYSTEM OR ELSEWHERE • Perform the Spark Test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].) • Is a strong blue spark visible at the suspected cylinder?	Yes	Go to Step 12.
No	Go to the next step.
10	INSPECT SPARK PLUG • Turn the ignition switch off. • Remove the suspected spark plug. (See SPARK PLUG REMOVAL/INSTALLATION [L3 Turbo].) • Inspect the suspected spark plug. (See SPARK PLUG INSPECTION [L3 Turbo].) • Is there any malfunction?	Yes	Replace the suspected spark plug, then go to Step 14. (See SPARK PLUG REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
11	INSPECT IGNITION COIL • Inspect the suspected ignition coil. (See IGNITION COIL INSPECTION [L3 Turbo].) • Is there any malfunction?	Yes	Replace the suspected ignition coil, then go to Step 14. (See IGNITION COIL REMOVAL/INSTALLATION [L3 Turbo].)
No	Inspect the suspect cylinder ignition coil related wiring harness. • Repair or replace the suspected wiring harness, if necessary. Go to Step 14.
12	INSPECT ENGINE COMPRESSION • Inspect the engine compression. (See COMPRESSION INSPECTION [L3 Turbo].) • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.
No	Go to the next step.
13	INSPECT FUEL INJECTOR OPERATION • Access the INJ_1, INJ_2, INJ_3, INJ_4 PIDs. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].) • Start the engine and warm it up to the normal operating temperature. • Turn the fuel injector off from on using the PID simulation function. • Does the engine speed decrease while the fuel injectors are turned off?	Yes	Go to the next step.
No	Inspect the fuel injector for engine speed does not decrease fuel injector. (See FUEL INJECTOR INSPECTION [L3 Turbo].) • If there is no malfunction: ― Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION [L3 Turbo].) • If there is any malfunction: ― Repair or replace the malfunctioning part according to the inspection results. Go to the next step.
14	VERIFY DTC TROUBLESHOOTING COMPLETED • Make sure to reconnect all disconnected connectors. • Start the engine. • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [L3 Turbo].) • Perform the KOER self test. (See KOEO/KOER SELF TEST [L3 Turbo].) • Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [L3 Turbo].)
No	Go to the next step.
15	VERIFY AFTER REPAIR PROCEDURE • Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [L3 Turbo].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L3 Turbo].)
No	DTC troubleshooting completed.

STEP

INSPECTION

ACTION

VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED

• Have the snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (misfire related) been recorded?

Yes

Go to the next step.

Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to the next step.

VERIFY RELATED SERVICE INFORMATION AVAILABILITY

• Verify related Service Information availability.

• Is any related Service Information available?

Yes

Perform repair or diagnosis according to the available Service Information.

• If the vehicle is not repaired, go to the next step.

Go to the next step.

VERIFY RELATED PENDING CODE AND STORED DTC

• Turn the ignition switch off, then to the ON position (engine off).

• Perform the DTC Reading Procedure and Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Are any other DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [L3 Turbo].)

Go to the next step.

VERIFY CURRENT INPUT SIGNAL STATUS (KEY TO ON/IDLE)

• Access the following PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

― APP1

― APP2

― ECT

― IAT

― MAF

― RPM

― TP REL

― VSS

• Is there any signal that is far out of specification when the ignition switch is turned to the ON position and the engine idles? (See PCM INSPECTION [L3 Turbo].)

Yes

Inspect the suspected circuit.

• If the inspection results are normal:

― Go to the next step.

• If the inspection results are not normal:

― Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.

Go to the next step.

VERIFY CURRENT INPUT SIGNAL STATUS UNDER FREEZE FRAME DATA (MODE 2) CONDITION

• Access the same PIDs as in Step 4 while simulating the FREEZE FRAME DATA (Mode 2) condition. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Is there any signal which causes drastic changes?

Yes

Inspect the suspected circuit.

• If the inspection results are normal:

― Go to the next step.

• If the inspection results are not normal:

― Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.

Go to the next step.

INSPECT INTAKE-AIR SYSTEM FOR AIR SUCTION

• Inspect for air leakage at the following:

― Around connection of dynamic chamber and intake manifold

― Around connection of intake manifold and cylinder head

Note

• Engine speed may change when rust penetrating agent is sprayed on the air suction area.

• Is air leakage found?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.

Go to the next step.

INSPECT SEALING OF ENGINE COOLANT PASSAGE

• Perform the “ENGINE COOLANT LEAKAGE INSPECTION”. (See ENGINE COOLANT LEAKAGE INSPECTION [L3 Turbo].)

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.

Go to the next step.

INSPECT FUEL INJECTOR WIRING HARNESS

• Remove the intake air system parts. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3 Turbo].)

• Disconnect the fuel injector connector on suspected cylinder.

• Connect the NOID LIGHT to the fuel injector terminals.

• Inspect dim of light during cranking.

• Does the light illuminate?

Yes

Go to the next step.

Inspect the fuel injector wiring harnesses.

• Repair or replace the suspected wiring harness, if necessary.

Go to Step 14.

INSPECT WHETHER MALFUNCTION IS IN IGNITION SYSTEM OR ELSEWHERE

• Perform the Spark Test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L3 Turbo].)

• Is a strong blue spark visible at the suspected cylinder?

Yes

Go to Step 12.

Go to the next step.

INSPECT SPARK PLUG

• Turn the ignition switch off.

• Remove the suspected spark plug. (See SPARK PLUG REMOVAL/INSTALLATION [L3 Turbo].)

• Inspect the suspected spark plug. (See SPARK PLUG INSPECTION [L3 Turbo].)

• Is there any malfunction?

Yes

Replace the suspected spark plug, then go to Step 14.

(See SPARK PLUG REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

INSPECT IGNITION COIL

• Inspect the suspected ignition coil. (See IGNITION COIL INSPECTION [L3 Turbo].)

• Is there any malfunction?

Yes

Replace the suspected ignition coil, then go to Step 14.

(See IGNITION COIL REMOVAL/INSTALLATION [L3 Turbo].)

Inspect the suspect cylinder ignition coil related wiring harness.

• Repair or replace the suspected wiring harness, if necessary.

Go to Step 14.

INSPECT ENGINE COMPRESSION

• Inspect the engine compression. (See COMPRESSION INSPECTION [L3 Turbo].)

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 14.

Go to the next step.

INSPECT FUEL INJECTOR OPERATION

• Access the INJ_1, INJ_2, INJ_3, INJ_4 PIDs. (See ON-BOARD DIAGNOSTIC TEST [L3 Turbo].)

• Start the engine and warm it up to the normal operating temperature.

• Turn the fuel injector off from on using the PID simulation function.

• Does the engine speed decrease while the fuel injectors are turned off?

Yes

Go to the next step.

Inspect the fuel injector for engine speed does not decrease fuel injector.

(See FUEL INJECTOR INSPECTION [L3 Turbo].)

• If there is no malfunction:

― Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION [L3 Turbo].)

• If there is any malfunction:

― Repair or replace the malfunctioning part according to the inspection results.

Go to the next step.

VERIFY DTC TROUBLESHOOTING COMPLETED

• Make sure to reconnect all disconnected connectors.

• Start the engine.

• Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [L3 Turbo].)

• Perform the KOER self test. (See KOEO/KOER SELF TEST [L3 Turbo].)

• Is the PENDING CODE for this DTC present?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [L3 Turbo].)

Go to the next step.

VERIFY AFTER REPAIR PROCEDURE

• Perform the “AFTER REPAIR PROCEDURE”. (See AFTER REPAIR PROCEDURE [L3 Turbo].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [L3 Turbo].)

DTC troubleshooting completed.