
9 CHECK INJECTOR
1. Disconnect all ignition coil harness connectors.
2. Place pans or saucers under each injector.
3. Crank engine for about 3 seconds. Make sure that fuel sprays out from injectors.
SEF595Q
Fuel should be sprayed evenly for each cylinder.
OK or NG
OK©GO TO 10.
NG©Replace injectors from which fuel does not spray out. Always replace O-ring with new
one.
10 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-144.
©INSPECTION END
DTC P0171 FUEL INJECTION SYSTEM FUNCTION (LEAN SIDE)QG
Diagnostic Procedure (Cont'd)
EC-254

On Board Diagnosis LogicNJEC0192With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensor 1 (front).
The ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
Sensor Input Signal to ECMECM func-
tionActuator
Heated oxygen sensor 1 (front)Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injec-
tion & mix-
ture ratio
controlInjectors
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0172
0172+Fuel injection system does not operate properly.
+The amount of mixture ratio compensation is too large.
(The mixture ratio is too rich.)+Heated oxygen sensor 1 (front)
+Injectors
+Exhaust gas leaks
+Incorrect fuel pressure
+Mass air flow sensor
SEF215Z
SEF058Y
DTC Confirmation ProcedureNJEC0193NOTE:
If ªDTC Confirmation Procedure º has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Turn ignition switch ªONº and select ªSELF-LEARN CON-
TROLº in ªWORK SUPPORTº mode with CONSULT-II.
4) Clear the self-learning control coefficient by touching ªSTARTº.
5) Select ªDATA MONITORº mode with CONSULT-II.
6) Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0172 should be detected at this stage, if a
malfunction exists. If so, go to ªDiagnostic Procedureº,
EC-258.
7) If it is difficult to start engine at step 6, the fuel injection sys-
tem has a malfunction.
8) Crank engine while depressing accelerator pedal. If engine
starts, go to ªDiagnostic Procedureº, EC-258. If engine does
not start, remove ignition plugs and check for fouling, etc.
JEF105Y
With GST
1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 9 seconds.
3) Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 3 seconds at idle speed.
4) Stop engine and reconnect mass air flow sensor harness con-
nector.
5) Select ªMODE 7º with GST. Make sure 1st trip DTC P0100 is
detected.
6) Select ªMODE 4º with GST and erase the 1st trip DTC P0100.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
On Board Diagnosis Logic
EC-255

6 CHECK FUNCTION OF INJECTORS
With CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Perform ªPOWER BALANCEº in ªACTIVE TESTº mode with CONSULT-II.
SEF190Y
4. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-II
1. Install all parts removed.
2. Start engine.
3. Listen to each injector operating sound.
MEC703B
Clicking noise should be heard.
OK or NG
OK©GO TO 7.
NG©Perform trouble diagnosis for ªINJECTORSº, EC-447.
7 REMOVE INJECTOR
1. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
2. Turn ignition switch ªOFFº.
3. Remove injector assembly. Refer to EC-39.
Keep fuel hose and all injectors connected to injector gallery.
©GO TO 8.
8 CHECK INJECTOR
1. Disconnect all injector harness connectors.
2. Disconnect all ignition coil harness connectors.
3. Prepare pans or saucers under each injectors.
4. Crank engine for about 3 seconds.
Make sure fuel does not drip from injector.
OK or NG
OK (Does not drip)©GO TO 9.
NG (Drips)©Replace the injectors from which fuel is dripping. Always replace O-ring with new one.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure (Cont'd)
EC-260

On Board Diagnosis LogicNJEC0202If a misfire occurs, the engine speed will fluctuate. If the fluctuation is detected by the crankshaft position sen-
sor (POS), the misfire is diagnosed.
Sensor Input Signal to ECM ECM function
Crankshaft position sensor (POS) Engine speed On board diagnosis of misfire
The misfire detection logic consists of the following two conditions.
1. One Trip Detection Logic (Three Way Catalyst Damage)
When a misfire is detected which will overheat and damage the three way catalyst, the MI will start blink-
ing; even during the first trip. In this condition, ECM monitors the misfire every 200 revolutions.
If the misfire frequency decreases to a level that will not damage the three way catalyst, the MI will change
from blinking to lighting up. (After the first trip detection, the MI will light up from engine starting. If a mis-
fire is detected that will cause three way catalyst damage, the MI will start blinking.)
2. Two Trip Detection Logic (Exhaust quality deterioration)
When a misfire that will not damage the three way catalyst (but will affect exhaust emission) occurs, the
MI will light up based on two trip detection logic. In this condition, ECM monitors the misfire for every 1,000
revolutions of the engine.
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0300
0300+Multiple cylinders misfire.+Improper spark plug
+Insufficient compression
+Incorrect fuel pressure
+EGR volume control valve
+The injector circuit is open or shorted
+Injectors
+Intake air leak
+Insufficient ignition spark
+Lack of fuel
+Heated oxygen sensor 1 (front) P0301
0301+No. 1 cylinder misfires.
P0302
0302+No. 2 cylinder misfires.
P0303
0303+No. 3 cylinder misfires.
P0304
0304+No. 4 cylinder misfires.
SEF058Y
DTC Confirmation ProcedureNJEC0203CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 9 seconds
before conducting the next test.
With CONSULT-II
1) Turn ignition switch ªONº, and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and warm it up to normal operating temperature.
3) Turn ignition switch ªOFFº and wait at least 9 seconds.
4) Start engine again and drive at 1,500 - 3,000 rpm for at least
3 minutes.
Hold the accelerator pedal as steady as possible.
NOTE:
Refer to the freeze frame data for the test driving conditions.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-263.
With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0300 - P0304 NO.4-1CYLINDER MISFIRE, MULTIPLE CYLINDER
MISFIRE
QG
On Board Diagnosis Logic
EC-262

5 CHECK INJECTORS
1. Refer to Wiring Diagram for Injectors, EC-447.
2. Stop engine and then turn ignition switch ªONº.
3. Check voltage between ECM terminals 101, 103, 105 and 107 and ground with CONSULT-II or tester.
SEF075X
Battery voltage should exist.
OK or NG
OK©GO TO 6.
NG©Perform ªDiagnostic Procedureº INJECTOR, EC-448.
6 CHECK IGNITION SPARK
1. Disconnect ignition coil assembly from rocker cover.
2. Connect a known good spark plug to the ignition coil assembly.
3. Place end of spark plug against a suitable ground and crank engine.
4. Check for spark.
SEF575Q
OK or NG
OK©GO TO 7.
NG©Check ignition coil, power transistor and their circuits. Refer to EC-451.
7 CHECK INJECTOR
1. Turn ignition switch ªOFFº.
2. Remove injector assembly. Refer to EC-39.
Keep fuel hose and all injectors connected to injector gallery.
3. Disconnect camshaft position sensor harness connector.
4. Turn ignition switch ªONº.
Make sure fuel does not drip from injector.
OK or NG
OK (Does not drip)©GO TO 8.
NG (Drips)©Replace the injector(s) from which fuel is dripping.
DTC P0420 THREE WAY CATALYST FUNCTIONQG
Diagnostic Procedure (Cont'd)
EC-302

SEF138X
Component DescriptionNJEC0435The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the injector circuit, the coil in the injector is
energized. The energized coil pulls the needle valve back and
allows fuel to flow through the injector into the intake manifold. The
amount of fuel injected depends upon the injection pulse duration.
Pulse duration is the length of time the injector remains open. The
ECM controls the injection pulse duration based on engine fuel
needs.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0436
MONITOR ITEM CONDITION SPECIFICATION
INJ PULSE-B1+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 2.0 - 3.5 msec
2,000 rpm 1.5 - 3.5 msec
B/FUEL SCHDL+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 1.5 - 3.0 msec
2,000 rpm 1.2 - 3.0 msec
ECM Terminals and Reference ValueNJEC0437Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
101
103
105
107R/B
Y/B
G/B
L/BInjector No. 1
Injector No. 2
Injector No. 3
Injector No. 4[Engine is running]
+Warm-up condition
+Idle speedBATTERY VOLTAGE
(11 - 14V)
SEF011W
[Engine is running]
+Warm-up condition
+Engine speed is 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
SEF012W
INJECTORQG
Component Description
EC-446
![NISSAN ALMERA N16 2001 Electronic Repair Manual EGR Volume Control Valve (Where Fitted)NJEC0560
Terminal No. ResistanceW[at 20ÉC (68ÉF)]
1-2
20-24 2-3
4-5
5-6
EGR Temperature Sensor (Where Fitted)NJEC0472
EGR temperature
ÉC (ÉF)Voltage
VResista NISSAN ALMERA N16 2001 Electronic Repair Manual EGR Volume Control Valve (Where Fitted)NJEC0560
Terminal No. ResistanceW[at 20ÉC (68ÉF)]
1-2
20-24 2-3
4-5
5-6
EGR Temperature Sensor (Where Fitted)NJEC0472
EGR temperature
ÉC (ÉF)Voltage
VResista](/manual-img/5/57351/w960_57351-785.png)
EGR Volume Control Valve (Where Fitted)NJEC0560
Terminal No. ResistanceW[at 20ÉC (68ÉF)]
1-2
20-24 2-3
4-5
5-6
EGR Temperature Sensor (Where Fitted)NJEC0472
EGR temperature
ÉC (ÉF)Voltage
VResistance
MW
0 (32) 4.56 0.62 - 1.05
50 (122) 2.25 0.065 - 0.094
100 (212) 0.59 0.011 - 0.015
EVAP Canister Purge Volume Control ValveNJEC0481
Resistance [at 20ÉC (68ÉF)]W31-35
IACV-AAC ValveNJEC0474
Terminal No. ResistanceW[at 20ÉC (68ÉF)]
1-2
20-24 2-3
4-5
5-6
InjectorNJEC0475
Resistance [at 25ÉC (77ÉF)]W13.5 - 17.5
Ignition Coil with Power TransistorNJEC0561
Terminal No. (Polarity) ResistanceW[at 25ÉC (77ÉF)]
3 (+) - 2 (þ) Except 0 or¥
1 (+) - 3 (þ)
Except 0
1 (+) - 2 (þ)
CondenserNJEC0587
Resistance [at 25ÉC (77ÉF)] MWAbove 1
Fuel PumpNJEC0473
Resistance [at 25ÉC (77ÉF)]W0.2 - 5.0
SERVICE DATA AND SPECIFICATIONS (SDS)QG
EGR Volume Control Valve (Where Fitted)
EC-490

NJEL0311
Use the chart below to find out what each wiring
diagram code stands for.
Refer to the wiring diagram code in the alphabetical
index to find the location (page number) of each
wiring diagram.
Code Section Wiring Diagram Name
ISTSIG AT A/T 1ST Signal
2NDSIG AT A/T 2ND Signal
3RDSIG AT A/T 3RD Signal
4THSIG AT A/T 4TH Signal
A/C, M HA Manual Air Conditioner
A/CCUT EC Air Conditioner Cut Control
AAC/V EC IACV-AAC Valve
AACVLV EC IACV-AAC Valve
ABS BR Anti-lock Brake System
APS EC Accelerator Position Sensor
AT/C EC A/T Control
ATCONT EC A/T Control
ATDIAG EC A/T Diagnosis Communication Line
AUDIO EL Audio
BA/FTS AT A/T Fluid Temperature Sensor and
TCM Power Supply
BACK/L EL Back-up Lamp
BRK/SW EC Brake Pedal Position Switch
CHARGE SC Charging System
CHIME EL Warning Chime
CIGAR EL Cigarette Lighter
CKPS EC Crankshaft Position Sensor (POS)
CKPS EC Crankshaft Position Sensor (TDC)
CLOCK EL Clock
COOL/F EC Cooling Fan Control
D/LOCK EL Power Door Lock
DEF EL Rear Window Defogger
DTRL EL Headlamp Ð With Daytime Light
System
ECMRLY EC ECM Relay
ECTS EC Engine Coolant Temperature Sensor
EGR/TS EC EGR Temperature Sensor
EGRC1 EC EGR Function
EGVC/V EC EGR Volume Control Valve
ENGSS AT Engine Speed Signal
Code Section Wiring Diagram Name
F/FOG EL Front Fog Lamp
F/PUMP EC Fuel Pump
FRO2 EC Front Heated Oxygen Sensor (Non
E-OBD)
FRO2/H EC Front Heated Oxygen Sensor Heater
(Non E-OBD)
FTS AT A/T Fluid Temperature Sensor
FUEL EC Fuel Injection System Function
GLOW EC Glow Control System
H/AIM EL Headlamp Aiming Control System
H/LAMP EL Headlamp
H/SEAT EL Heated Seat
HEATER HA Heater System
HLC EL Headlamp Washer
HORN EL Horn
IATS EC Intake Air Temperature Sensor
IATSEN EC Intake Air Temperature Sensor
IGN/SG EC Ignition Signal
ILL EL Illumination
INJECT EC Injector
INJPMP EC Injection Pump
INT/L EL Spot, Vanity Mirror, Personal and
Trunk Room Lamps
IVC EC Intake Valve Timing Control Solenoid
Valve
IVC/V EC Intake Valve Timing Control Solenoid
Valve
KS EC Knock Sensor
LOAD EC Load Signal
LPSV AT Line Pressure Solenoid Valve
MAFS EC Mass Air Flow Sensor
MAIN AT Main Power Supply and Ground Cir-
cuit
MAIN EC Main Power Supply and Ground Cir-
cuit
METER EL Speedometer, Tachometer, Temp.
and Fuel Gauges
MIL/DL EC MIL and Data Link Connectors
MIRROR EL Door Mirror
MULTI EL Multi-remote Control System
NATS EL Nissan Anti-Theft System
WIRING DIAGRAM CODES (CELL CODES)
EL-367