Nissan Sentra. Manual - part 394

EC-272

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

P0300, P0301, P0302, P0303, P0304 MISFIRE

Is the inspection result normal?

YES

>> GO TO 7.

NO

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

EC-456, "Diagnosis Procedure"

.

7.

CHECK SPARK PLUG

Check the initial spark plug for fouling, etc. Refer to 

EM-45,

"Removal and Installation"

.

Is the inspection result normal?

YES

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

spark plug type, refer to 

EM-118, "Spark Plug"

.

NO

>> 1. Repair or clean spark plug.

2. GO TO 8.

8.

CHECK FUNCTION OF IGNITION COIL-3

1. Reconnect the initial spark plugs. Refer to 

EM-45, "Removal and Installation"

.

2. Crank engine for about 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-118, "Spark

Plug"

.

9.

CHECK COMPRESSION PRESSURE

Check compression pressure. Refer to 

EM-23, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

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

EM-112,

"Description"

.

10.

CHECK FUEL PRESSURE

1. Install all removed parts.

2. Release fuel pressure to zero. Refer to 

EC-143, "Work Procedure"

.

3. Install fuel pressure gauge and check fuel pressure. Refer to 

EC-143, "Work Procedure"

.

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, "Exploded View"

.

NO

>> Repair or replace error-detected parts.

12.

CHECK IGNITION TIMING

Check ignition timing. Refer to 

EC-480, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> Perform “BASIC INSPECTION”. Refer to 

EC-131, "Work Procedure"

.

13.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect A/F sensor 1 harness connector.

SEF156I

Spark should be generated.

P0300, P0301, P0302, P0303, P0304 MISFIRE

EC-273

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

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3. Disconnect ECM harness connector.

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

*1: Except California

*2: For California

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

*1: Except California

*2: For California

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

YES

>> GO TO 14.

NO

>> Repair or replace error-detected parts.

14.

CHECK A/F SENSOR 1 HEATER

Check the A/F sensor 1 heater. Refer to 

EC-177, "Component Inspection (A/F Sensor 1 Heater)"

.

Is the inspection result normal?

YES

>> GO TO 15.

NO

>> Replace A/F sensor 1. Refer to 

EM-30, "Exploded View"

.

15.

CHECK MASS AIR FLOW SENSOR

With CONSULT

Check “MASS AIRFLOW” in “DATA MONITOR” mode of “ENGINE” using CONSULT.

With GST

Check mass air flow sensor signal in Service $01 with GST.

Is the measurement value within the specification?

YES

>> GO TO 16.

NO

>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or

ground. Refer to 

EC-186, "DTC Logic"

.

+

−

Continuity

A/F sensor 1

ECM

Connector

Terminal

Connector

Terminal

F12

*1

F42

*2

1

F24

41

Existed

2

45

+

−

Continuity

A/F sensor 1

Connector

Terminal

F12

*1

F42

*2

1

Ground

Not existed

2

+

−

Continuity

ECM

Connector

Terminal

F24

41

Ground

Not existed

45

Specification

: 

EC-486, "Mass Air Flow 

Sensor"

Specification

: 

EC-486, "Mass Air Flow 

Sensor"

EC-274

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

P0300, P0301, P0302, P0303, P0304 MISFIRE

16.

CHECK SYMPTOM TABLE

Check items on the rough idle symptom in 

EC-473, "Symptom Table"

.

Is the inspection result normal?

YES

>> GO TO 17.

NO

>> Repair or replace error-detected parts.

17.

ERASE THE 1ST TRIP DTC

Some tests may cause a 1st trip DTC to be set.

Erase the 1st trip DTC from the ECM memory after performing the tests. Refer to 

EC-55, "Diagnosis Descrip-

tion"

.

>> GO TO 18.

18.

CHECK INTERMITTENT INCIDENT

Perform 

GI-39, "Intermittent Incident"

.

>> INSPECTION END

P0327, P0328 KS

EC-275

< DTC/CIRCUIT DIAGNOSIS >

[MRA8DE]

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P0327, P0328 KS

DTC Logic

INFOID:0000000009758521

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting the next test.

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.

TESTING CONDITION:

Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and run it for at least 5 seconds at idle speed.

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

YES

>> Proceed to 

EC-275, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009758522

1.

CHECK KNOCK SENSOR GROUND CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect knock sensor harness connector.

3. Disconnect ECM harness connector.

4. Check the continuity between knock sensor harness connector and ECM harness connector.

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

YES

>> GO TO 2.

NO

>> Repair or replace error-detected parts.

2.

CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT

1. Check the continuity between knock sensor harness connector and ECM harness connector.

DTC No.

CONSULT screen terms

(Trouble diagnosis con-

tent)

DTC detecting condition

Possible cause

P0327

KNOCK SEN/CIRC-B1
(Knock sensor 1 circuit 
low bank 1)

An excessively low voltage from the knock sen-
sor is sent to ECM.

• Harness or connectors

(Knock sensor circuit is open or short-
ed.)

• Knock sensor

P0328

KNOCK SEN/CIRC-B1
(Knock sensor 1 circuit 
high bank 1)

An excessively high voltage from the knock 
sensor is sent to ECM.

+

−

Continuity

Knock sensor

ECM

Connector

Terminal

Connector

Terminal

F8

2

F24

8

Existed