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CO-1
ENGINE
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SECTION CO
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CONTENTS
ENGINE COOLING SYSTEM
PRECAUTION ....... ........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Liquid Gasket .....................................3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tool ........................................... ......4
Commercial Service Tool ..........................................4
FUNCTION DIAGNOSIS ...............................6
COOLING SYSTEM ....................................... .....6
Cooling Circuit ..................................................... ......6
Schematic .................................................................7
OVERHEATING CAUSE ANALYSIS ..................8
Troubleshooting Chart ...............................................8
ON-VEHICLE MAINTENA NCE ....................10
ENGINE COOLANT ....................................... ....10
Inspection ............................................................ ....10
Changing Engine Coolant .......................................11
RADIATOR ........................................................14
Checking Radiator ............................................... ....14
ON-VEHICLE REPAIR .................................15
RADIATOR ....... .................................................15
Exploded View ..................................................... ....15
Removal and Installation .........................................15
ENGINE COOLING FAN ...................................18
Exploded View .........................................................18
Removal and Installation (Crankshaft Driven
Type) .......................................................................
18
Removal and Installation (Motor Driven Type) ........19
WATER PUMP ..................................................20
Exploded View .........................................................20
Removal and Installation .........................................20
THERMOSTAT AND WATER PIPING ..............22
Exploded View .........................................................22
Removal and Installation .........................................22
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
24
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
24
Standard and Limit .............................................. ....24
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CO-8
< FUNCTION DIAGNOSIS >
OVERHEATING CAUSE ANALYSIS
OVERHEATING CAUSE ANALYSIS
Troubleshooting ChartINFOID:0000000005149040
SymptomCheck items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat stuck closed Coolant circulation
Damaged fins
Dust contamination or pa-
per clogging
Physical damage
Clogged radiator cooling
tube Excess foreign material
(rust, dirt, sand, etc.)
Water cut valve malfunction Excess foreign material
(rust, dirt, sand, etc.), phys-
ical damage
Reduced air flow Cooling fan does not oper-
ate
Fan assembly —
High resistance to fan rota-
tion
Damaged fan blades
Damaged radiator shroud —Radiator shroud —
Improper engine coolant
mixture ratio —
Coolant viscosity —
Poor engine coolant quality —Engine coolant density —
Insufficient engine coolant Engine coolant leaksCooling hose
Loose clamp
Cracked hose
Water pump Poor sealing
Radiator cap Loose
Poor sealing
Radiator O-ring for da
mage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tank Exhaust gas leaks into cool-
ing system Cylinder head deterioration
Cylinder head gasket deteri-
oration
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CO-20
< ON-VEHICLE REPAIR >
WATER PUMP
WATER PUMP
Exploded ViewINFOID:0000000005149049
Removal and InstallationINFOID:0000000005149050
CAUTION:
• When removing water pump, be careful not to get engine coolant on drive belt.
• Water pump cannot be disassembled and should be replaced as a unit.
REMOVAL
1. Drain engine coolant from the radiator. Refer to CO-11, "Changing Engine Coolant".
CAUTION:
Perform when the engine is cold.
2. Remove the engine cooling fan (crankshaft driven type). Refer to CO-18, "
Removal and Installation
(Crankshaft Driven Type)".
3. Remove the water pump pulley.
4. Remove the water pump. • Engine coolant will leak from the cylinder block, so have a receptacle ready below.
CAUTION:
Handle water pump vane so that it does not contact any other parts.
INSPECTION AFTER REMOVAL
• Visually check that there is no signi ficant dirt or rust on the water
pump body and vane.
• Make sure there is no looseness in the vane shaft, and that it turns smoothly when rotated by hand.
• Replace the water pump assembly, if necessary.
INSTALLATION
Installation is in the reverse order of removal.
• After installation bleed the air from the cooling system. Refer to CO-11, "
Changing Engine Coolant".
1. Gasket2. Water pump3. Water pump pulley
KBIA2543E
KBIA2552E
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WATER PUMPCO-21
< ON-VEHICLE REPAIR >
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INSPECTION AFTER INSTALLATION
• Check for leaks of engine coolant. Refer to
CO-10, "Inspection".
• Start and warm up engine. Visually c heck for leaks of the engine coolant.
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EC-184
< COMPONENT DIAGNOSIS >[VK56DE]
P0181 FTT SENSOR
>> Repair open circuit or short to power in harness or connector.
5.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-184, "
Component Inspection".
OK or NG
OK >> GO TO 6.
NG >> Replace “fuel level sensor unit and fuel pump”.
6.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000005149200
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 3 and 4 by heating with hot water as shown in the fig-
ure.
If NG, replace fuel level sensor unit.
Temperature °C ( °F)] Resistance (kΩ)
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
SEF476YA
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P0182, P0183 FTT SENSOREC-187
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INSPECTION END
Component InspectionINFOID:0000000005149205
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 3 and 4 by heating with hot water as shown in the fig-
ure.
If NG, replace fuel level sensor unit.
Temperature °C ( °F)] Resistance (kΩ )
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
SEF476YA
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![INFINITI QX56 2010 Factory Service Manual P0442 EVAP CONTROL SYSTEMEC-221
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4. Using EVAP leak detector, locate the EVAP leak. For the leak
detector, refer to the instruction manu INFINITI QX56 2010 Factory Service Manual P0442 EVAP CONTROL SYSTEMEC-221
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4. Using EVAP leak detector, locate the EVAP leak. For the leak
detector, refer to the instruction manu](/manual-img/42/57032/w960_57032-1573.png)
P0442 EVAP CONTROL SYSTEMEC-221
< COMPONENT DIAGNOSIS > [VK56DE]
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4. Using EVAP leak detector, locate the EVAP leak. For the leak
detector, refer to the instruction manual for more details.
Refer to EC-37, "
Description".
OK or NG
OK >> GO TO 8.
NG >> Repair or replace.
7.CHECK FOR EVAP LEAK
Without CONSULT-III
1. Turn ignition switch OFF.
2. Apply 12 volts DC to EVAP canister vent control valve. The valve will close. (Continue to apply 12 volts
until the end of test.)
3. Pressurize the EVAP line using pressure pump with 1.3 to 2.7 kPa (10 to 20 mmHg, 0.39 to 0.79 inHg), then remove pump and EVAP service port adapter.
CAUTION:
• Never use compressed air or a high pressure pump.
• Do not exceed 4.12 kPa (0.042 kg/cm
2, 0.6 psi) of pressure in the system.
4. Using EVAP leak detector, locate the EVAP leak. For the leak detector, refer to the instruction manual for more details. Refer
to EC-37, "
Description".
OK or NG
OK >> GO TO 8.
NG >> Repair or replace.
8.CHECK EVAP CANISTER VENT CONTROL VALVE
Check the following.
• EVAP canister vent control valve is installed properly. Refer to EC-493, "
Removal and Installation".
• EVAP canister vent control valve. Refer to EC-236, "
Component Inspection".
OK or NG
OK >> GO TO 9.
NG >> Repair or replace EVAP canister vent control valve and O-ring.
9.CHECK IF EVAP CANISTER SATURATED WITH WATER
1. Remove EVAP canister with EVAP canister vent c ontrol valve and EVAP control system pressure sensor
attached.
SEF200U
BBIA0443E
SEF200U
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![INFINITI QX56 2010 Factory Service Manual P0451 EVAP CONTROL SYSTEM PRESSURE SENSOREC-243
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace g INFINITI QX56 2010 Factory Service Manual P0451 EVAP CONTROL SYSTEM PRESSURE SENSOREC-243
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace g](/manual-img/42/57032/w960_57032-1595.png)
P0451 EVAP CONTROL SYSTEM PRESSURE SENSOREC-243
< COMPONENT DIAGNOSIS > [VK56DE]
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Refer to
EC-85, "Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR CONNECTOR FOR WATER
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check sensor harness connector for water.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace harness connector.
3.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR
Refer to EC-243, "
Component Inspection".
OK or NG
OK >> GO TO 4.
NG >> Replace EVAP control system pressure sensor.
4.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
For wiring diagram, refer to EC-246, "
Diagnosis Procedure".
>> INSPECTION END
Component InspectionINFOID:0000000005149266
EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Remove EVAP control system pr essure sensor with its harness connector connected from EVAP canister.
Always replace O-ring with a new one.
2. Install a vacuum pump to EVAP control system pressure sensor.
BBIA0354E
Water should not exist.
BBIA0443E
Revision: April 20092010 QX56