2007 INFINITI M35 engine hose

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-147
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Revision: 2007 April2007 M35/M45
5. CHANGE ENGINE OIL
1. Stop the engine.
2. Change engine oil.
NOTE:
This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detected after changing engine oil or changing driving con-
dition.
>>INSPECTION END
6. CHECK FUEL PRESSURE
Check fuel pressure. (Refer to EC-88, "
Fuel Pressure Check" .)
OK or NG
OK >> GO TO 9.
NG (Fuel pressure is too high)>>Replace fuel pressure regulator, refer to EC-89, "
FUEL PRESSURE
CHECK" . GO TO 8.
NG (Fuel pressure is too low)>>GO TO 7.
7. DETECT MALFUNCTIONING PART
1. Check the following.
–Clogged and bent fuel hose and fuel tube
–Clogged fuel filter
–Fuel pump and its circuit (Refer to EC-675, "FUEL PUMP" .)
2. If NG, repair or replace the malfunctioning part. (Refer to EC-89, "
FUEL PRESSURE CHECK" .)
If OK, replace fuel pressure regulator.
>> GO TO 8.
8. 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 9.
9. PERFORM POWER BALANCE TEST
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Make sure that the each cylinder produces a momentary engine
speed drop.
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
PBIB0133E

EC-228
[VQ35DE]
DTC P0125 ECT SENSOR
Revision: 2007 April2007 M35/M45
3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace thermostat. Refer to CO-29, "
WATER INLET AND THERMOSTAT ASSEMBLY"
.
4. CHECK INTERMITTENT INCIDENT
Refer to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Refer to EC-216, "
Wiring Diagram" .
>>INSPECTION END
Component InspectionNBS004VV
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.

2. If NG, replace engine coolant temperature sensor.
Removal and InstallationNBS004VW
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-31, "WATER OUTLET AND WATER PIPING" .
PBIB2005E
Temperature°C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

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" .

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-309
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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
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Revision: 2007 April2007 M35/M45
Diagnostic ProcedureNBS004XV
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

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
EC-319
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Revision: 2007 April2007 M35/M45
9. CHECK FUNCTION OF FUEL INJECTOR-II
Provide battery voltage between the following terminals, 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-669, "
FUEL INJECTOR" .
10. CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Reconnect all harness connectors disconnected.
4. Disconnect all fuel injector harness connectors.
5. Remove fuel tube assembly. Refer to EM-47, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all fuel injectors connected to fuel tube.
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-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
CylinderHarness connector F221 terminal
(+) (–)
1
56
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32
43
51
67
Operating sound should exist.
PBIB2497E
Fuel should be sprayed evenly for each fuel injector.
PBIB1726E

EC-330
[VQ35DE]
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
9. CHECK FUNCTION OF FULE INJECTOR-II
Provide battery voltage between the following terminals, 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-669, "
FUEL INJECTOR" .
10. CHECK FUEL INJECTOR
1. Remove fuel injector assembly. Refer to EM-47, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all fuel injectors connected to fuel tube.
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Reconnect all harness connectors disconnected.
4. Disconnect all fuel injector harness connectors.
5. Disconnect all ignition coil harness connectors.
6. Prepare pans or saucers under each fuel injectors.
7. Crank engine for about 3 seconds.
Make sure fuel does not drip from fuel injector.
OK or NG
OK (Does not drip.)>>GO TO 11.
NG (Drips.)>>Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one.
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
CylinderHarness connector F221 terminal
(+) (–)
1
56
24
32
43
51
67
Operating sound should exist.
PBIB2497E

DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
EC-349
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Revision: 2007 April2007 M35/M45
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
PFP:00000
On Board Diagnosis LogicNBS004YM
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the crank-
shaft position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is occurring.
The misfire detection logic consists of the following two conditions.
1. One Trip Detection Logic (Three Way Catalyst Damage)
On the 1st trip that a misfire condition occurs that can damage the three way catalyst (TWC) due to over-
heating, the MIL will blink.
When a misfire condition occurs, the ECM monitors the CKP sensor signal every 200 engine revolutions
for a change.
When the misfire condition decreases to a level that will not damage the TWC, the MIL will turn off.
If another misfire condition occurs that can damage the TWC on a second trip, the MIL will blink.
When the misfire condition decreases to a level that will not damage the TWC, the MIL will remain on.
If another misfire condition occurs that can damage the TWC, the MIL will begin to blink again.
2. Two Trip Detection Logic (Exhaust quality deterioration)
For misfire conditions that will not damage the TWC (but will affect vehicle emissions), the MIL will only
light when the misfire is detected on a second trip. During this condition, the ECM monitors the CKP sen-
sor signal every 1,000 engine revolutions.
A misfire malfunction can be detected on any one cylinder or on multiple cylinders.
DTC Confirmation ProcedureNBS004YN
CAUTION:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws when driv-
ing.
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.
Sensor Input signal to ECM ECM function
Crankshaft position sensor (POS) Engine speed On board diagnosis of misfire
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0300
0300Multiple cylinder misfire
detectedMultiple cylinder misfire.

Improper spark plug

Insufficient compression

Incorrect fuel pressure

The fuel injector circuit is open or
shorted

Fuel injector

Intake air leak

The ignition signal circuit is open or
shorted

Lack of fuel

Signal plate

A/F sensor 1

Incorrect PCV hose connection P0301
0301No.1 cylinder misfire
detectedNo. 1 cylinder misfires.
P0302
0302No. 2 cylinder misfire
detectedNo. 2 cylinder misfires.
P0303
0303No. 3 cylinder misfire
detectedNo. 3 cylinder misfires.
P0304
0304No. 4 cylinder misfire
detectedNo. 4 cylinder misfires.
P0305
0305No. 5 cylinder misfire
detectedNo. 5 cylinder misfires.
P0306
0306No. 6 cylinder misfire
detectedNo. 6 cylinder misfires.