fuel pressure INFINITI M35 2007 Factory Workshop Manual

EC-148
[VQ35DE]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2007 April2007 M35/M45
10. DETECT MALFUNCTIONING PART
1. Check the following.
–Ignition coil and its circuit (Refer to EC-691, "IGNITION SIGNAL" .)
–Fuel injector and its circuit (Refer to EC-669, "FUEL INJECTOR" .)
–Intake air leakage
–Low compression pressure (Refer to EM-102, "CHECKING COMPRESSION PRESSURE" .)
2. If NG, repair or replace the malfunctioning part.
If OK, replace fuel injector. (It may be caused by leakage from fuel injector or clogging.)
>> GO TO 11.
11 . CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 12.
12. CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.

For DTC P0130, P0150, refer to EC-234, "DTC Confirmation Procedure" .

For DTC P0131, P0151, refer to EC-244, "DTC Confirmation Procedure" .

For DTC P0132, P0152, refer to EC-253, "DTC Confirmation Procedure" .

For DTC P0133, P0153, refer to EC-263, "DTC Confirmation Procedure" .

For DTC P2A00, P2A03, refer to EC-646, "DTC Confirmation Procedure" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13. CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 15.
15. DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
>> GO TO 16.

EC-262
[VQ35DE]
DTC P0133, P0153 A/F SENSOR 1
Revision: 2007 April2007 M35/M45
DTC P0133, P0153 A/F SENSOR 1PFP:22693
Component DescriptionNBS004WU
The air fuel ratio (A/F) sensor 1 is a planar dual-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is the combination of a
Nernst concentration cell (sensor cell) with an oxygen-pump cell,
which transports ions. It has a heater in the element.
The sensor is capable of precise measurement = 1, but also in the
lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide range (0.7 <
< air).
The exhaust gas components diffuse through the diffusion gap at the
electrode of the oxygen pump and Nernst concentration cell, where
they are brought to thermodynamic balance.
An electronic circuit controls the pump current through the oxygen-
pump cell so that the composition of the exhaust gas in the diffusion
gap remains constant at = 1. Therefore, the A/F sensor 1 is able to
indicate air/fuel ratio by this pumping of current. In addition, a heater
is integrated in the sensor to ensure the required operating tempera-
ture of 700 - 800°C (1,292 - 1,472°F).
CONSULT-II Reference Value in Data Monitor ModeNBS004WV
Specification data are reference values.
On Board Diagnosis LogicNBS004WW
To judge the malfunction of A/F sensor 1, this diagnosis measures response time of the A/F signal computed
by ECM from the A/F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel
feedback control constant, and the A/F sensor 1 temperature index. Judgment is based on whether the com-
pensated time (the A/F signal cycling time index) is inordinately long or not.
SEF579Z
SEF580Z
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)

Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 1.5 V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P0133
0133
(Bank 1)
Air fuel ratio (A/F) sensor 1
circuit slow response

The response of the A/F signal computed by
ECM from A/F sensor 1 signal takes more than
the specified time.

Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)

A/F sensor 1

A/F sensor 1 heater

Fuel pressure

Fuel injector

Intake air leaks

Exhaust gas leaks

PCV

Mass air flow sensor P0153
0153
(Bank 2)

EC-264
[VQ35DE]
DTC P0133, P0153 A/F SENSOR 1
Revision: 2007 April2007 M35/M45

Intake air leaks

Exhaust gas leaks

Incorrect fuel pressure

Lack of fuel

Fuel injector

Incorrect PCV hose connection

PCV valve

Mass air flow sensor
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
6. Let engine idle for 1 minute.
7. Increase the engine speed up to 4,000 to 5,000 rpm and keep it for 10 seconds.
8. Fully release accelerator pedal and then let engine idle for about 1 minute.
9. Select Service $07 with GST.
If the 1st trip DTC is displayed, go to EC-268, "
Diagnostic Procedure" .

EC-274
[VQ35DE]
DTC P0137, P0157 HO2S2
Revision: 2007 April2007 M35/M45
DTC P0137, P0157 HO2S2PFP:226A0
Component DescriptionNBS004X1
The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeNBS004X2
Specification data are reference values.
On Board Diagnosis LogicNBS004X3
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxy-
gen storage capacity of the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the maximum voltage of the sensor is suf-
ficiently high during the various driving condition such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following conditions
are met
–Engine: After warming up
–Keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF259VA
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0137
0137
(Bank 1)
Heated oxygen sensor
2 circuit low voltageThe maximum voltage from the sensor is not
reached to the specified voltage.

Harness or connectors
(The sensor circuit is open or shorted)

Heated oxygen sensor 2

Fuel pressure

Fuel injector

Intake air leaks P0157
0157
(Bank 2)

EC-286
[VQ35DE]
DTC P0138, P0158 HO2S2
Revision: 2007 April2007 M35/M45
DTC Confirmation ProcedureNBS004XD
Perform PROCEDURE FOR MALFUNCTION A first.
If DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR MALFUNCTION A
With CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 2 minutes.
6. If 1st trip DTC is detected, go to EC-291, "
PROCEDURE FOR
MALFUNCTION A" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION B
With CONSULT-II
TESTING CONDITION:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1146” (for DTC P0138) or “HO2S2 (B2) P1166” (for DTC P0158) of “HO2S2” in
“DTC WORK SUPPORT” mode with CONSULT-II.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0138
0138
(Bank 1)
Heated oxygen sensor
2 circuit high voltageA)An excessively high voltage from the sen-
sor is sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted)

Heated oxygen sensor 2
P0158
0158
(Bank 2)B)The minimum voltage from the sensor is
not reached to the specified voltage.

Harness or connectors
(The sensor circuit is open or shorted)

Heated oxygen sensor 2

Fuel pressure

Fuel injector
SEF174Y
SEF174Y

EC-298
[VQ35DE]
DTC P0139, P0159 HO2S2
Revision: 2007 April2007 M35/M45
DTC P0139, P0159 HO2S2PFP:226A0
Component DescriptionNBS004XJ
The heated oxygen sensor 2, after three way catalyst 1, monitors the
oxygen level in the exhaust gas on each bank.
Even if switching characteristics of the air fuel ratio (A/F) sensor 1
are shifted, the air-fuel ratio is controlled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeNBS004XK
Specification data are reference values.
On Board Diagnosis LogicNBS004XL
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxy-
gen storage capacity of the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the switching response of the sensor's
voltage is faster than specified during the various driving condition
such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following conditions
are met
–Engine: After warming up
–Keeping engine speed between 3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF302U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0139
0139
(Bank 1)
Heated oxygen sensor
2 circuit slow responseIt takes more time for the sensor to respond
between rich and lean than the specified time.

Harness or connectors
(The sensor circuit is open or shorted)

Heated oxygen sensor 2

Fuel pressure

Fuel injector

Intake air leaks P0159
0159
(Bank 2)

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-309
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS004XS
With 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 A/F sensors 1. The ECM calcu-
lates 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 lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureNBS004XT
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-II.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Select “DATA MONITOR” mode with CONSULT-II.
6. Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0171 or P0174 should be detected at this
stage, if a malfunction exists. If so, go to EC-315, "
Diagnostic
Procedure" .
NOTE:
If 1st trip DTC is not detected during above procedure, perform-
ing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to
(1st trip) Freeze Frame Data for 10 minutes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
Sensor Input signal to ECM ECM function Actuator
A/F sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection control Fuel injector
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0171
0171
(Bank 1)
Fuel injection system too
lean

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)

Intake air leaks

A/F sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Lack of fuel

Mass air flow sensor

Incorrect PCV hose connection P0174
0174
(Bank 2)
SEF968Y
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)
Engine coolant temperature
(T) conditionWhen 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).

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-317
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
4. CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-88, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-89, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Fuel pump and circuit (Refer to EC-675, "FUEL PUMP" .)

Fuel pressure regulator (Refer to EC-89, "FUEL PRESSURE CHECK" .)

Fuel lines (Refer to FL-3, "FUEL SYSTEM" .)

Fuel filter for clogging
>> Repair or replace.
6. CHECK MASS AIR FLOW SENSOR
With CONSULT-II
1. Install all removed parts.
2. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-II.
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in Service $01 with GST.
OK or NG
OK (With CONSULT-II)>>GO TO 7.
OK (Without CONSULT-II)>>GO TO 8.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
grounds. Refer to EC-193, "
DTC P0101 MAF SENSOR" .
7. CHECK FUNCTION OF FUEL INJECTOR
With CONSULT-II
1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with
CONSULT-II.
3. Make sure that each circuit produces a momentary engine
speed drop.
OK or NG
OK >> GO TO 10.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-669, "
FUEL INJECTOR" . At idling: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
PBIB0133E

EC-320
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS004XW
With 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 A/F sensors 1. The ECM calcu-
lates 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).
DTC Confirmation ProcedureNBS004XX
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-II.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Select “DATA MONITOR” mode with CONSULT-II.
6. Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0172, P0175 should be detected at this stage,
if a malfunction exists. If so, go to EC-326, "
Diagnostic Proce-
dure" .
NOTE:
If 1st trip DTC is not detected during above procedure, perform-
ing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to
(1st trip) Freeze Frame Data for 10 minutes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
7. If it is difficult to start engine at step 6, the fuel injection system has a malfunction, too.
8. Crank engine while depressing accelerator pedal.
Sensor Input signal to ECM ECM function Actuator
A/F sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection control Fuel injector
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0172
0172
(Bank 1)
Fuel injection system too
rich

Fuel injection system does not operate properly.

The amount of mixture ratio compensation is too
large. (The mixture ratio is too rich.)

A/F sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Mass air flow sensor P0175
0175
(Bank 2)
SEF968Y
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)
Engine coolant temperature
(T) conditionWhen 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).

EC-328
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
4. CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-88, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-89, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Fuel pump and circuit (Refer to EC-675, "FUEL PUMP" .)

Fuel pressure regulator (Refer to EC-89, "FUEL PRESSURE CHECK" .)
>> Repair or replace.
6. CHECK MASS AIR FLOW SENSOR
With CONSULT-II
1. Install all removed parts.
2. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-II.
With GST
1. Install all removed parts.
2. Check mass air flow sensor signal in “Service $01” with GST.
OK or NG
OK (With CONSULT-II)>>GO TO 7.
OK (Without CONSULT-II)>>GO TO 8.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
grounds. Refer to EC-193, "
DTC P0101 MAF SENSOR" .
7. CHECK FUNCTION OF FUEL INJECTOR
With CONSULT-II
1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with
CONSULT-II.
3. Make sure that each circuit produces a momentary engine
speed drop.
OK or NG
OK >> GO TO 10.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-669, "
FUEL INJECTOR" . At idling: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
PBIB0133E