Page 340 of 720
EC-340
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS00077
1. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst 1.
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.
PBIB1922E
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
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3. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding A/F sensor 1 harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals.
Refer to Wiring Diagram.
5. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
6. Also check harness for short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-79, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-80, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
1. A/F sensor 1 harness connector
(bank 1)2. A/F sensor 1 harness connector
(bank 2)
:Vehicle front
Bank 1A/F sensor 1 terminal ECM terminal
157
261
Bank 2165
266
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
157165
261266
Continuity should not exist.
PBIB3516E
At idling: Approximately 350 kPa (3.57 kg/cm2 , 51 psi)
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EC-342
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 November2007 350Z
5. DETECT MALFUNCTIONING PART
Check the following.
Fuel pump and circuit (Refer to EC-691, "FUEL PUMP" .)
Fuel pressure regulator (Refer to EC-80, "FUEL PRESSURE CHECK" .)
>> Repair or replace.
6. CHECK MASS AIR FLOW SENSOR
With CONSULT-III
1. Install all removed parts.
2. Start engine and warm it up to normal temperature.
3. Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-III.
With GST
1. Install all removed parts.
2. Start engine and warm it up to normal temperature.
3. Check mass air flow sensor signal in Service $01 with GST.
OK or NG
OK >> GO TO 7.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-197, "
DTC P0101, P010B MAF SENSOR" .
7. CHECK FUNCTION OF FUEL INJECTOR
With CONSULT-III
1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-III.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine and let it idle.
2. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 8.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-686, "
FUEL INJECTOR" . 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
Clickng sound should be heard.
PBIB3332E
Page 344 of 720

EC-344
DTC P0181 FTT SENSOR
Revision: 2006 November2007 350Z
DTC P0181 FTT SENSORPFP:22630
Component DescriptionNBS00078
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.
*: This data is reference values and is measured between ECM terminal 106 (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 LogicNBS00079
DTC Confirmation ProcedureNBS0007A
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-III
1. Turn ignition switch ON and wait at least 10 seconds.
2. Check 1st trip DTC.
If 1st trip DTC is detected, go to EC-346, "
Diagnostic Procedure" .
If 1st trip DTC is not detected, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-III.
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. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-346, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
PBIB1665E
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
Page 345 of 720
DTC P0181 FTT SENSOR
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Revision: 2006 November2007 350Z
Wiring DiagramNBS0007B
TBWT1640E
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EC-346
DTC P0181 FTT SENSOR
Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS0007C
1. CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-47, "
SELF-DIAGNOSTIC RESULTS" .
OK or NG
OK >> GO TO 2.
NG >> Go to DI-19, "
Fuel Level Sensor Signal Inspection" .
2. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect “fuel level sensor unit and fuel pump” harness con-
nector.
2. Turn ignition switch ON.
3. Check voltage between “fuel level sensor unit and fuel pump”
terminal 4 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors B1, M12
Harness for open or short between ECM and “fuel level sensor unit and fuel pump”
>> Repair open circuit or short to ground or short to power in harness or connector.
4. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “unified meter and A/C amp.” harness connector M49.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
PBIB1665E
Voltage: Approximately 5V
PBIB0932E
Continuity should exist.
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DTC P0181 FTT SENSOR
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5. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors B1, M12
Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C
amp.”
>> Repair open circuit or short to ground or short to power in harness or connector.
6. CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-347, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace fuel level sensor unit.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionNBS0007D
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water as shown in the fig-
ure.
3. If NG, replace fuel level sensor unit.
Removal and InstallationNBS0007E
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Temperature °C (°F) Resistance kΩ
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E
Page 348 of 720

EC-348
DTC P0182, P0183 FTT SENSOR
Revision: 2006 November2007 350Z
DTC P0182, P0183 FTT SENSORPFP:22630
Component DescriptionNBS0007F
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.
*: This data is reference values and is measured between ECM terminal 106 (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 LogicNBS0007G
DTC Confirmation ProcedureNBS0007H
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-III
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-350, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
PBIB1665E
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
P0182
0182Fuel tank temperature
sensor circuit low inputAn excessively low voltage from the sensor is
sent to ECM.
Harness or connectors
(The sensor circuit is open or shorted.)
Fuel tank temperature sensor P0183
0183Fuel tank temperature
sensor circuit high inputAn excessively high voltage from the sensor is
sent to ECM.