INFINITI FX35 2006 Service Manual

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION EC-307
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
Wiring DiagramNBS003P6
BANK 1
TBWM1384E

EC-308
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 December 2006 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) TER-
MINAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
2R/L A/F sensor 1 heater
(bank 1) [Engine is running]

Warm-up condition

Idle speed Approximately 5V
16 G A/F sensor 1 (bank 1) [Engine is running]

Warm-up condition

Idle speed Approximately 3.1V
35 B/R Approximately 2.6V
56 L Approximately 2.3V
75 R/B Approximately 2.3V
21
22
23 W
G
R Fuel injector No. 5
Fuel injector No. 3
Fuel injector No. 1 [Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idle BATTERY VOLTAGE
(11 - 14V)
[Engine is running]

Warm-up condition

Engine speed: 2,000 rpm BATTERY VOLTAGE
(11 - 14V)
PBIB1584E
SEC984C
SEC985C

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION EC-309
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
BANK 2
TBWM1385E

EC-310
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 December 2006 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) TER-
MINAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
24 L A/F sensor 1 heater
(bank 2) [Engine is running]

Warm-up condition

Idle speed Approximately 5V
40
41
42 LG
B
P Fuel injector No. 6
Fuel injector No. 4
Fuel injector No. 2 [Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idle BATTERY VOLTAGE
(11 - 14V)
[Engine is running]

Warm-up condition

Engine speed: 2,000 rpm BATTERY VOLTAGE
(11 - 14V)
57 G A/F sensor 1 (bank 2) [Engine is running]

Warm-up condition

Idle speed Approximately 2.6V
58 Y Approximately 2.3V
76 P Approximately 3.1V
77 BR Approximately 2.3V
PBIB1584E
SEC984C
SEC985C

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION EC-311
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
Diagnostic ProcedureNBS003P7
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
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.
PBIB1922E

EC-312
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 December 2006 FX35/FX45
3. CHECK AIR FUEL RATIO (A/F) SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect corresponding air fuel ration (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 ground and 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.
A/F sensor 1 terminal ECM terminal
Bank 1 116
275
535
656
Bank 2 176
277
557
658
Continuity should exist.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 116176
275277
535557
656658
Continuity should not exist.
PBIB2190E

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION EC-313
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
4. CHECK FUEL PRESSURE
1. Release fuel pressure to zero. Refer to EC-86, "
FUEL PRESSURE RELEASE" .
2. Install fuel pressure gauge and check fuel pressure. Refer to EC-87, "
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-635, "FUEL PUMP" .)

Fuel pressure regulator (Refer to EC-87, "FUEL PRESSURE CHECK" )

Fuel lines (Refer to FL-3, "Checking Fuel Lines" .)

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 COUSULT-II)>>GO TO 8.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or ground. Refer to EC-188, "
DTC P0101 MAF SENSOR" .
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

EC-314
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 December 2006 FX35/FX45
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-628, "
FUEL INJECTOR" .
PBIB0133E

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION EC-315
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Revision: 2006 December 2006 FX35/FX45
8. CHECK FUNCTION OF FUEL INJECTOR-I
Without CONSULT-II
1. Turn ignition switch OFF.
2. Disconnect harness connectors F50, F251
3. Turn ignition switch ON.
4. Check voltage between harness connector F50 terminal 5 and ground with CONSULT-II or tester.
5. Turn ignition switch OFF.
6. Disconnect ECM harness connector.
7. Check harness continuity between harness connector F50 and ECM as follows.
Refer to Wiring Diagram.
8. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-628, "
FUEL INJECTOR" .
PBIB2624E
Voltage: Battery voltage
Cylinder Harness connector F50
terminal ECM terminal
1623
2442
3222
4341
5121
6740
Continuity should exist.
PBIB2323E

EC-316
[VQ35DE]
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2006 December 2006 FX35/FX45
9. CHECK FUNCTION OF FUEL INJECTOR-II
Provide battery voltage between harness connector F251 as follows
and then interrupt it. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 10.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-628, "
FUEL INJECTOR" .
10. CHECK FUEL INJECTOR
1. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
2. Turn ignition switch OFF.
3. Reconnect all harness connectors disconnected.
4. Disconnect all fuel injector harness connectors.
5. Remove fuel injector gallery assembly. Refer to EM-45, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all fuel injectors connected to fuel injector gallery.
6. For DTC P0171, reconnect fuel injector harness connectors on bank 1. For DTC P0174, reconnect fuel injector harness connectors on bank 2.
7. Disconnect all ignition coil harness connectors.
8. Prepare pans or saucers under each fuel injector.
9. Crank engine for about 3 seconds. For DTC P0171, make sure that fuel sprays out from fuel injec-
tors on bank 1.
For DTC P0174, make sure that fuel sprays out from fuel injec-
tors on bank 2.
OK or NG
OK >> GO TO 11.
NG >> Replace fuel injectors from which fuel does not spray out. Always replace O-ring with new ones.
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-148, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Cylinder Harness connector F251 terminal
(+) (–)
156
254
352
453
551
657
Operating sound should exist.
PBIB2497E
Fuel should be sprayed evenly for each fuel injector.
PBIB1726E