Nissan Pathfinder. Manual - part 492

EC-274

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

3. Turn ignition switch ON.

4. Turn ignition switch OFF and wait at least 10 seconds.

5. Restart engine and let it idle for approximately 15 minutes.

6. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Proceed to 

EC-275, "Diagnosis Procedure"

.

NO

>> GO TO 3.

3.

PERFORM DTC CONFIRMATION PROCEDURE-II

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

4. Start engine and drive the vehicle under similar conditions to (1st trip) Freeze Frame Data for a certain

time. Refer to the table below.

Hold the accelerator pedal as steady as possible.

Similar conditions to (1st trip) Freeze Frame Data mean that the following conditions should be satisfied at

the same time.

CAUTION:

Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws when

driving.

Driving time varies according to the engine speed in the freeze frame data.

5. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Proceed to 

EC-275, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009178190

1.

CHECK FOR INTAKE AIR LEAKAGE AND PCV HOSE

1. Start engine and run it at idle speed.

2. Listen for the sound of the intake air leakage.

3. Check PCV hose connection.
Is intake air leakage detected?

YES

>> Discover air leakage location and repair.

NO

>> GO TO 2.

2.

CHECK FOR EXHAUST SYSTEM CLOGGING

Stop engine and visually check exhaust tube, three way catalyst and muffler for dents.
Is the inspection result normal?

YES-1 >> With CONSULT: GO TO 3.

YES-2 >> Without CONSULT: GO TO 4.

NO

>> Repair or replace malfunctioning part.

Engine speed

Engine speed in the freeze frame data 

± 400 rpm

Vehicle speed

Vehicle speed in the freeze frame data 

± 10 km/h (6 MPH)

Basic fuel schedule

Basic fuel schedule in freeze frame data 

× (1 ± 0.1)

Engine coolant temperature (T) 
condition

When the freeze frame data shows lower than 70

°C (158°F),

T should be lower than 70

°C (158°F).

When the freeze frame data shows higher than or equal to 70

°C (158°F),

T should be higher than or equal to 70

°C (158°F).

Engine speed

Time

Around 1,000 rpm

Approximately 10 minutes

Around 2,000 rpm

Approximately 5 minutes

More than 3,000 rpm

Approximately 3.5 minutes

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

EC-275

< DTC/CIRCUIT DIAGNOSIS >

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3.

PERFORM POWER BALANCE TEST

 With CONSULT

1. Start engine.

2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT.

3. Check that each circuit produces a momentary engine speed drop.
Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 4.

4.

CHECK FUNCTION OF FUEL INJECTOR

1. Start engine and let it idle.

2. Listen to each fuel injector make operation sound.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Perform trouble diagnosis for FUEL INJECTOR, refer to

EC-430, "Diagnosis Procedure"

.

5.

CHECK FUNCTION OF IGNITION COIL-I

CAUTION:

Perform the following procedure in a place with no combustible objects and good ventilation.

1. Turn ignition switch OFF.

2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.

NOTE:

Do not use CONSULT to release fuel pressure, or fuel pressure applies again during the following proce-

dure.

3. Start engine.

4. After engine stalls, crank it 2 or 3 times to release all fuel pressure.

5. Turn ignition switch OFF.

6. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.

7. Remove ignition coil and spark plug of the cylinder to be checked.

8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.

9. Connect spark plug and harness connector to ignition coil.

10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 -

0.66 in) between the edge of the spark plug and grounded metal

portion as shown in the figure.

11. Crank engine for approximately 3 seconds, and check whether

spark is generated between the spark plug and the grounded

metal portion.

CAUTION:

• During the operation, always stay 0.5 m (19.7 in) or more

away from the spark plug and the ignition coil. Be careful

not to get an electrical shock while checking, because the

electrical discharge voltage becomes 20 kV or more.

• It might damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.

NOTE:

When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunc-

tioning.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 6.

Clicking sound should be heard.

PBIB3332E

Spark should be generated.

JMBIA0066GB

EC-276

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

6.

CHECK FUNCTION OF IGNITION COIL-II

1. Turn ignition switch OFF.

2. Disconnect spark plug and connect a non-malfunctioning spark plug.

3. Crank engine for approximately 3 seconds, and recheck whether spark is generated between the spark

plug and the grounded metal portion.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Check ignition coil, power transistor and their circuits. Refer to 

EC-437, "Diagnosis Procedure"

.

7.

CHECK SPARK PLUG

Check the initial spark plug for fouling, etc.
Is the inspection result normal?

YES

>> Replace spark plug(s) with standard type one(s). For

spark plug type, refer to 

EM-134, "Spark Plug"

.

NO

>> Repair or clean spark plug. Then GO TO 8.

8.

CHECK FUNCTION OF IGNITION COIL-III

1. Reconnect the initial spark plugs.

2. Crank engine for approximately 3 seconds, and recheck whether spark is generated between the spark

plug and the grounded portion.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace spark plug(s) with standard type one(s). For spark plug type, refer to 

EM-134, "Spark

Plug"

.

9.

CHECK COMPRESSION PRESSURE

Check compression pressure. Refer to 

EM-22, "On-Vehicle Service"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.

10.

CHECK FUEL PRESSURE

1. Install all removed parts.

2. Release fuel pressure to zero. Refer to 

EC-151, "Work Procedure"

.

3. Install fuel pressure gauge kit [SST: — (J-44321)] and check fuel pressure. Refer to 

EC-151, "Work Proce-

dure"

.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> GO TO 11.

11.

DETECT MALFUNCTIONING PART

Check fuel hoses and fuel tubes for clogging.
Is the inspection result normal?

YES

>> Replace “fuel filter and fuel pump assembly”. Refer to 

FL-6, "Removal and Installation"

.

Spark should be generated.

SEF156I

Spark should be generated.

At idle: Approximately 350 kPa (3.57 kg/cm

2

, 51 psi)

P0300, P0301, P0302, P0303, P0304, P0305, P0306 MISFIRE

EC-277

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

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NO

>> Repair or replace malfunctioning part.

12.

CHECK IGNITION TIMING

Check idle speed and ignition timing.

For procedure, refer to 

EC-147, "Work Procedure"

.

For specification, refer to 

EC-467, "Idle Speed"

 and 

EC-467, "Ignition Timing"

.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> Follow the 

EC-147, "Work Procedure"

.

13.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect corresponding A/F sensor 1 harness connector.

3. Disconnect ECM harness connector.

4. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

5. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector

and ground.

6. Also check harness for short to power.
Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Repair open circuit, short to ground or short to power in harness or connectors.

14.

CHECK A/F SENSOR 1 HEATER

Check A/F sensor 1 heater. Refer to 

EC-184, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 15.

NO

>> Replace malfunctioning A/F sensor 1. Refer to 

EM-31, "Removal and Installation (bank 2)"

, 

EM-

33, "Removal and Installation (bank 1)"

.

15.

CHECK MASS AIR FLOW SENSOR

With CONSULT

A/F sensor 1

ECM

Continuity

Bank

Connector

Terminal

Connector

Terminal

1

F5

1

F52

69

Existed

2

73

2

F65

1

77

2

81

A/F sensor 1

Ground

Continuity

Bank

Connector

Terminal

1

F5

1

Ground

Not existed

2

2

F65

1

2

ECM

Ground

Continuity

Connector

Terminal

F52

69

Ground

Not existed

73

77

81