check engine INFINITI FX35 2004 Service Manual

EC-914
[VK45DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicABS00C3U
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 heated oxygen sensors 1. 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 lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureABS00C3V
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-918, "
Diagnostic
Procedure" .
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. If engine
starts, go to EC-918, "
Diagnostic Procedure" . If engine does not
start, check exhaust and intake air leak visually.
Sensor Input signal to ECM ECM function Actuator
Heated oxygen sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection
controlFuel injector
DTC No.Trouble diagnosis
nameDTC 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

Heated oxygen 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

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-915
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Revision: 2004 November 2004 FX35/FX45
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Select MODE 3 with GST. Make sure DTC P0102 is detected.
6. Select MODE 4 with GST and erase the DTC P0102.
7. Start engine again and let it idle for at least 10 minutes.
8. Select MODE 7 with GST. The 1st trip DTC P0171 or P0174
should be detected at this stage, if a malfunction exists. If so, go
to EC-918, "
Diagnostic Procedure" .
9. If it is difficult to start engine at step 7, the fuel injection system
has a malfunction.
10. Crank engine while depressing accelerator pedal. If engine starts, go to EC-918, "
Diagnostic Procedure" .
If engine does not start, check exhaust and intake air leak visually.
PBIB1502E

EC-918
[VK45DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureABS00C3X
1. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK FOR INTAKE AIR LEAK
1. Listen for an intake air leak after the mass air flow sensor.
2. Check PCV hose connection.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
SEC502D

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-921
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Revision: 2004 November 2004 FX35/FX45
7. CHECK FUNCTION OF INJECTORS
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.
Without CONSULT-II
1. Start engine.
2. Listen to each injector operating sound.
OK or NG
OK >> GO TO 8.
NG >> Perform trouble diagnosis for EC-1274, "
INJECTOR CIRCUIT" .
8. CHECK INJECTOR
1. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
2. Turn ignition switch OFF.
3. Disconnect all injector harness connectors.
4. Remove injector gallery assembly. Refer to EM-188, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all injectors connected to injector gallery.
5. For DTC P0171, reconnect injector harness connectors on bank 1.
For DTC P0174, reconnect injector harness connectors on bank 2.
6. Disconnect all ignition coil harness connectors.
7. Prepare pans or saucers under each injector.
8. Crank engine for about 3 seconds.
For DTC P0171, make sure that fuel sprays out from injectors
on bank 1.
For DTC P0174, make sure that fuel sprays out from injectors
on bank 2.
OK or NG
OK >> GO TO 9.
NG >> Replace injectors from which fuel does not spray out.
Always replace O-ring with new ones.
PBIB0133E
Clicking noise should be heard.
PBIB1986E
Fuel should be sprayed evenly for each injector.
PBIB1726E

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-923
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicABS00C3Y
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 heated oxygen sensors 1. 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).
DTC Confirmation ProcedureABS00C3Z
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 or P0175 should be detected at this
stage, if a malfunction exists. If so, go to EC-927, "
Diagnostic
Procedure" .
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.
If engine starts, go to EC-927, "
Diagnostic Procedure" .
If engine does not start, remove ignition plugs and check for
fouling, etc.
Sensor Input signal to ECM ECM function Actuator
Heated oxygen sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection
controlFuel injector
DTC No.Trouble diagnosis
nameDTC 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.)

Heated oxygen sensor 1

Fuel injector

Exhaust gas leaks

Incorrect fuel pressure

Mass air flow sensor P0175
0175
(Bank 2)
SEF968Y

EC-924
[VK45DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor harness connector. Then
restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Select MODE 3 with GST. Make sure DTC P0102 is detected.
6. Select MODE 4 with GST and erase the DTC P0102.
7. Start engine again and let it idle for at least 10 minutes.
8. Select MODE 7 with GST. The 1st trip DTC P0172 or P0175
should be detected at this stage, if a malfunction exists. If so, go
to EC-927, "
Diagnostic Procedure" .
9. If it is difficult to start engine at step 7, the fuel injection system
has a malfunction.
10. Crank engine while depressing accelerator pedal.
If engine starts, go to EC-927, "
Diagnostic Procedure" . If engine does not start, remove ignition plugs and
check for fouling, etc.
PBIB1502E

DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-927
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureABS00C41
1. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
SEC502D

EC-930
[VK45DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2004 November 2004 FX35/FX45
7. CHECK FUNCTION OF INJECTORS
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.
Without CONSULT-II
1. Start engine.
2. Listen to each injector operating sound.
OK or NG
OK >> GO TO 8.
NG >> Perform trouble diagnosis for EC-1274, "
INJECTOR CIRCUIT" .
8. CHECK INJECTOR
1. Remove injector assembly. Refer to EM-188, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all injectors connected to injector gallery.
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Disconnect all injector harness connectors.
4. Disconnect all ignition coil harness connectors.
5. Prepare pans or saucers under each injectors.
6. 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.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
PBIB0133E
Clicking noise should be heard.
PBIB1986E

DTC P0181 FTT SENSOR
EC-931
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Revision: 2004 November 2004 FX35/FX45
DTC P0181 FTT SENSORPFP:22630
Component DescriptionABS00C42
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: These data are reference values and are measured between ECM terminal 107
(Fuel tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicABS00C43
DTC Confirmation ProcedureABS00C44
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. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 10 seconds.
If the result is NG, go to EC-934, "
Diagnostic Procedure" .
If the result is OK, go to following step.
4. Check “COOLAN TEMP/S” value.
If “COOLAN TEMP/S” is less than 60°C (140°F), the result will
be OK.
If “COOLAN TEMP/S” is above 60°C (140°F), go to the following
step.
5. Cool engine down until “COOLAN TEMP/S” is less than 60°C
(140°F).
6. Wait at least 10 seconds.
7. If 1st trip DTC is detected, go to EC-934, "
Diagnostic Procedure" .
PBIB1507E
Fluid temperature
°C (°F)Voltage*
VResistance
kΩ
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0181
0181Fuel tank temperature
sensor circuit range/
performanceRationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage sig-
nals from engine coolant temperature sensor
and intake air temperature sensor.

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

Fuel tank temperature sensor
SEF174Y

DTC P0222, P0223 TP SENSOR
EC-945
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Revision: 2004 November 2004 FX35/FX45
Specification 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.
Diagnostic ProcedureABS00C4L
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
47 LSensor power supply
(Throttle position sensor)[Ignition switch: ON]Approximately 5V
50 W Throttle position sensor 1[Ignition switch: ON]

Engine stopped

Shift lever: D

Accelerator pedal is fully releasedMore than 0.36V
[Ignition switch: ON]

Engine stopped

Shift lever: D

Accelerator pedal is fully depressedLess than 4.75V
66 BSensor ground
(Throttle position sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
69 R Throttle position sensor 2[Ignition switch: ON]

Engine stopped

Shift lever: D

Accelerator pedal is fully releasedLess than 4.75V
[Ignition switch: ON]

Engine stopped

Shift lever: D

Accelerator pedal is fully depressedMore than 0.36V
91 GSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
PBIB2195E