Nissan Frontier. Manual - part 473

ENGINE CONTROL SYSTEM SYMPTOMS

EC-463

< SYMPTOM DIAGNOSIS >

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C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

SYMPTOM

Reference 
page

HARD/NO ST

AR

T/REST

AR

T (EXCP

. 

HA)

E

N

GI

N

E

 ST

AL

L

HESIT

A

TION/S

U

R

GING/F

LA

T SP

OT

SP

ARK KNOCK/DE

T

O

NA

TION

LACK OF POWE

R/POOR

 ACCELERA

TIO

N

HIGH IDL

E/L

OW

 IDL

E

ROUG

H IDLE/HU

NTING

IDL

ING VIBRA

T

ION

SLO

W

/NO RETURN T

O

 IDLE

OVERHEA

T

S/W

A

TE

R

 TEMPERA

T

URE 

HIGH

EXCES

SIVE F

U

EL CONSUMP

T

ION

EXCES

SIVE OI

L CONSUMP

T

IO

N

BA

TTE

R

Y 

DEAD (UN

D

E

R

 CH

A

R

GE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG AH

AJ

AK

AL

AM HA

Fuel

Fuel tank

5

5

FL-6

Fuel piping

5

5

5

5

5

5

EM-39

Vapor lock

—

Valve deposit

5

5

5

5

5

5

5

—

Poor fuel (Heavy weight gasoline, 
Low octane)

—

Air

Air duct

5

5

5

5

5

5

EM-25

Air cleaner

EM-25

Air leakage from air duct
(Mass air flow sensor —electric 
throttle control actuator)

5

5

5

5

EM-25

Electric throttle control actuator

EC-194

Air leakage from intake manifold/
Collector/Gasket

EM-27

Cranking

Battery

1

1

1

1

1

1

1

1

PG-4

Generator circuit

CHG-2

 

(With EXP-
800 NI or 
GR8-1200 
NI), 

CHG-5

 

(Without 
EXP-800 
NI or GR8-
1200 NI)

Starter circuit

3

STR-6

 

(With GR8-
1200 NI), 

STR-10

 

(Without 
GR8-1200 
NI)

Signal plate/Flywheel/Drive plate

6

EM-77

Park/neutral position (PNP) 
switch (M/T)
TCM (A/T)

4

TM-170

EC-464

< SYMPTOM DIAGNOSIS >

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ENGINE CONTROL SYSTEM SYMPTOMS

1 - 6: The numbers refer to the order of inspection.

Engine

Cylinder head

5

5

5

5

5

5

5

5

EM-67

Cylinder head gasket

4

3

Cylinder block

6

6

6

6

6

6

6

6

4

EM-77

Piston

Piston ring

Connecting rod

Bearing

Crankshaft

Valve 
mecha-
nism

Timing chain

5

5

5

5

5

5

5

5

EM-45

Camshaft

EM-54

Intake valve timing control

EC-158

Intake valve

3

EM-67

Exhaust valve

Exhaust

Exhaust manifold/Tube/Muffler/
Gasket

5

5

5

5

5

5

5

5

EM-31

, 

EC-194

Three way catalyst

Lubrica-
tion

Oil pan/Oil strainer/Oil pump/Oil 
filter/Oil gallery

5

5

5

5

5

5

5

5

2

EM-33

, 

LU-

12

, 

LU-14

, 

LU-7

Oil level (Low)/Filthy oil

LU-9

Cooling

Radiator/Hose/Radiator filler cap

5

5

5

5

5

5

5

2

5

CO-16

Thermostat

5

CO-23

Water pump

CO-21

Water gallery

CO-7

Cooling fan

5

CO-19

Coolant level (low)/Contaminated 
coolant

CO-11

NVIS (NISSAN Vehicle Immobilizer System — 
NATS)

1

1

SEC-8

SYMPTOM

Reference 
page

HARD/NO S

TA

R

T/RES

TA

R

T (E

XCP

. HA)

E

N

GINE

 ST

ALL

HES

IT

A

TION/SURGING/FLA

T

 SPOT

S

P

ARK KNOC

K

/DET

O

NA

TI

ON

LACK OF 

POWER/POOR ACCELERA

TION

HIG

H

 IDL

E

/L

OW

 ID

LE

ROUGH IDLE/HUNTING

ID

LING VI

BRA

T

ION

S

LOW/NO RETU

RN 

T

O ID

LE

OVERHEA

T

S

/W

A

TER TEMPERA

T

URE HIG

H

E

XCESSIVE

 FUEL CON

S

UMP

T

ION

E

XCESSIVE

 OIL 

C

O

NSUMP

T

ION

B

A

TTER

Y 

DEAD (UNDER CHARGE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG AH

AJ

AK

AL

AM HA

NORMAL OPERATING CONDITION

EC-465

< SYMPTOM DIAGNOSIS >

[QR25DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

NORMAL OPERATING CONDITION

Fuel Cut Control (at No Load and High Engine Speed)

INFOID:0000000009481166

INPUT/OUTPUT SIGNAL CHART

*: This signal is sent to the ECM through CAN communication line.

SYSTEM DESCRIPTION

If the engine speed is above 2,000 rpm under no load (for example, the shift position is neutral and engine

speed is over 2,000 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies

based on engine speed.

Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will be cancelled.

NOTE:

This function is different from deceleration control listed under 

EC-33, "System Description"

.

Sensor

Input Signal to ECM

ECM function

Actuator

Park/neutral position (PNP) switch (M/T)
TCM (A/T)

Gear position

Fuel cut control Fuel injector

Accelerator pedal position sensor

Accelerator pedal position

Engine coolant temperature sensor

Engine coolant temperature

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed

Combination meter

Vehicle speed*

EC-466

< PERIODIC MAINTENANCE >

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FUEL PRESSURE

PERIODIC MAINTENANCE

FUEL PRESSURE

Fuel Pressure Check

INFOID:0000000009481167

FUEL PRESSURE RELEASE

 With CONSULT

1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in “WORK SUPPORT” mode with CONSULT.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.

 Without CONSULT

1. Remove fuel pump fuse located in IPDM E/R.
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel

pressure.

4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.

FUEL PRESSURE CHECK

CAUTION:

Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.

NOTE:

Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pres-

sure cannot be completely released because D40 models do not have fuel return system.

Method A

CAUTION:

• The fuel hose connection method used when taking fuel pressure check must not be used for other

purposes.

• Be careful not to scratch or put debris around connection area when servicing, so that the quick

connector maintains seal ability with O-rings inside.

• Never perform fuel pressure check with electrical systems operating (i.e. lights, A/C, etc.) Fuel pres-

sure gauge may indicate false readings due to varying engine load and changes in manifold vacuum.

1. Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
2. Prepare fuel hose for fuel pressure check, and connect fuel pressure gauge.

•  Use suitable fuel hose for fuel pressure check (genuine NISSAN fuel hose without quick connector).

• To avoid unnecessary force or tension to hose, use moderately long fuel hose for fuel pressure check.

• Never use the fuel hose for checking fuel pressure with damage or cracks on it.

• Use Pressure Gauge to check fuel pressure.

3. Remove fuel hose. Refer to 

EM-27, "Removal and Installation"

.

• Never twist or kink fuel hose because it is plastic hose.

• Never remove fuel hose from quick connector. 

• Keep the original fuel hose to be free from intrusion of dust or foreign substances with a suitable cover.

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