2008 INFINITI FX35 Cold Air Intake

ATC-80
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too low.  There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
 Liquid tank inlet and expan-
sion valve are frosted. Liquid tank inside is slightly
clogged.
 Replace liquid tank.
 Check lubricant for contami-
nation.
 Temperature of expansion valve inlet is extremely low
as compared with areas
near liquid tank.
 Expansion valve inlet is frosted.
 Temperature difference oc- curs somewhere in high-
pressure side. High-pressure pipe located be-
tween liquid tank and expan-
sion valve is clogged.
 Check and repair malfunc-
tioning parts.
 Check lubricant for contami- nation.
Expansion valve and liquid
tank are warm or slightly cool
when touched. Low refrigerant charge.
↓
Leaking fittings or compo-
nents.
Check refrigerant for leaks.
Refer to
ATC-138, "
Checking
of Refrigerant Leaks".
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specifica-
tion.
↓
1. Improper expansion
valve adjustment.
2. Malfunctioning expansion
valve.
3. Outlet and inlet may be clogged.  Remove foreign particles by
using compressed air.
 Replace expansion valve.
 Check lubricant for contami-
nation.
An area of the low-pressure
pipe is colder than areas near
the evaporator outlet. Low-pressure pipe is clogged
or crushed.  Check and repair malfunc-
tioning parts.
 Check lubricant for contami- nation.
Air flow volume is not enough
or is too low. Evaporator is frozen.  Check intake sensor circuit.
Refer to AT C - 9 4 , "
Intake
Sensor Circuit".
 Replace compressor.
 Repair evaporator fins.
 Replace evaporator.
Refer to AT C - 6 4 , "
Blower
Motor Circuit".
AC353A
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes be-
comes negative.  Air conditioning system does
not function and does not cy-
clically cool the compart-
ment air.
 The system constantly func- tions for a certain period of
time after compressor is
stopped and restarted. Refrigerant does not discharge
cyclically.
↓
Moisture is frozen at expan-
sion valve outlet and inlet.
↓
Water is mixed with refrigerant.
 Drain water from refrigerant
or replace refrigerant.
 Replace liquid tank.
AC354A
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REFRIGERANT LINESATC-141
< SERVICE INFORMATION >
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6. Do not stop when one leak is found. Continue to check for additional leaks at all system components.
If no leaks are found, perform steps 7 - 10.
7. Start the engine.
8. Set the A/C control as follows;
a. A/C switch: ON
b. Mode door position: VENT (Ventilation)
c. Intake position: Recirculation
d. Temperature setting: Max. cold
e. Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Stop the engine and perform leak check again following steps 4 through 6 above.
Refrigerant leaks should be chec ked immediately after stopping
the engine. Begin with the leak detector at the compressor. The
pressure on the high-pressure side will gradually drop after
refrigerant circulation stops and pressure on the low-pressure
side will gradually rise, as shown in the graph. Some leaks are
more easily detected when pressure is high.
11. Before connecting recovery/recycling recharging equipm ent to vehicle, check recovery/recycling recharg-
ing equipment gauges. No refrigerant pressure should be displayed. If pressure is displayed, recover
refrigerant from equipment lines and then check refrigerant purity.
12. Confirm refrigerant purity in supply tank using recovery/recycling recharging equipment and refrigerant
identifier.
13. Confirm refrigerant purity in vehicle A/C system us ing recovery/recycling recharging equipment and refrig-
erant identifier.
14. Discharge A/C system using approved refrigerant recove ry equipment. Repair the leaking fitting or com-
ponent if necessary.
15. Evacuate and recharge A/C system and perform the l eak test to confirm no refrigerant leaks.
16. Perform A/C performance test to ensure system works properly.
SHA839E
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WATER OUTLET AND WATER PIPINGCO-29
< SERVICE INFORMATION > [VQ35DE]
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WATER OUTLET AND WATER PIPING
ComponentINFOID:0000000001325860
Removal and InstallationINFOID:0000000001325861
REMOVAL
1. Remove front engine undercover with power tool.
2. Drain engine coolant from radiator drain plug at the
bottom of radiator, and from water drain plug at the
front of cylinder block. Refer to CO-10, "
Changing Engine Coolant" and CO-22, "Component".
CAUTION:
 Perform this step when the engine is cold.
 Do not spill engine coolant on drive belts.
3. Remove engine cover with power tool. Refer to EM-19, "
Component".
4. Remove air duct (inlet), air duct and air cleaner case assembly. Refer to EM-17, "
Component".
5. Remove radiator hose (upper) and heater hose.
6. Remove the following parts, when remove water outlet.  A/T fluid charging pipe: Refer to AT-241, "
Removal and Installation (2WD Models)".
 Intake manifold collectors (upper and lower). Refer to EM-19, "
Component".
 Rocker cover (right bank). Refer to EM-51, "
Component".
7. Remove engine coolant temperature sensor as necessary. CAUTION:
Be careful not to damage engi ne coolant temperature sensor.
8. Remove water outlet, heater pipe, water bypass hoses and water pipe.
INSTALLATION
1. Harness bracket 2. Water hose 3. Water bypass hose
4. Engine coolant temperature sensor 5. Gasket 6. Water outlet
7. Heater hose 8. Water pipe 9. Radiator hose (upper)
10. Heater pipe 11. Washer 12. O-ring
SBIA0484E
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THERMOSTAT AND WATER CONTROL VALVECO-53
< SERVICE INFORMATION > [VK45DE]
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 Refer to
GI-8, "Component" for symbols in the figure.
Removal and InstallationINFOID:0000000001325885
REMOVAL
1. Drain engine coolant from drain plugs on radiat or and both side of cylinder block. Refer to CO-37, "Chang-
ing Engine Coolant" and EM-242, "Disassembly and Assembly".
CAUTION:
 Perform this step when engine is cold.
 Do not spill engine coolant on drive belts.
2. Remove engine cover with power tool. Refer to EM-169, "
Component".
3. Remove air duct (inlet). Refer to EM-173, "
Component".
4. Disconnect water suction hose from water inlet.
5. Remove water inlet and thermostat. CAUTION:
Do not disassemble thermostat.
6. Remove intake manifolds (upper and lower). Refer to EM-175, "
Component".
7. Disconnect radiator hose (upper) and wa ter hoses from thermostat housing.
8. Disconnect heater hoses from water outlet and heater pipe.
9. Remove thermostat housing, water outlet pipe, water connector, water control valve, water outlet and heater pipe.
CAUTION:
Do not disassemble water control valve.
INSPECTION AFTER REMOVAL
 Make sure that valves both in thermostat and water c ontrol valve are completely closing at normal tempera-
ture.
 Place a thread so that it is caught in the valves of the thermostat
and water control valve. Immerse fully in a container filled with
water. Heat while stirring. (The example in the figure shows ther-
mostat.)
 The valve opening temperature is the temperature at which the valve opens and falls from the thread.
 Continue heating. Check the maximum valve lift. NOTE:
The maximum valve lift standard temperature for water control
valve is the reference value.
 After checking the maximum valve lift, lower the water tempera-
ture and check the valve closing temperature.
Standard values:
 If the malfunctioning condition, when closing valve at nor mal temperature, or measured values are out of the
standard, replace thermostat and/or water control valve.
INSTALLATION
Note the following, and install in the reverse order of removal.
CAUTION:
Be careful not to spill engine coolant over en gine room. Use rag to absorb engine coolant.
Thermostat and Water Control Valve
D. To heater core E. To cylinder head (left bank) F. To cylinder head (right bank)
G. To intake manifold adapter
SLC252B
Thermostat Water control valve
Valve opening temperature 80 - 84 °C (176 - 183 °F) 93.5 - 96.5 °C (200 - 206 °F)
Maximum valve lift More than 10 mm/95
°C
(0.39 in/203 °F) More than 8 mm/108
°C
(0.315 in/226 °F)
Valve closing temperature 77 °C (171 °F) 90 °C (194 °F)
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EC-94
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS

If DTC U1000 or U1001 is displayed with other DT C, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146
.
 If DTC U1010 is displayed with other DTC, fi rst perform the trouble diagnosis for DTC U1010.
Refer to EC-148
.
*: Models with ICC.Priority Detected items (DTC)
1  U1000 U1001 CAN communication line  U1010 CAN communication
 P0101 P0102 P0103 Mass air flow sensor
 P0112 P0113 P0127 Intake air temperature sensor
 P0117 P0118 P0125 Engine coolant temperature sensor
 P0128 Thermostat function
 P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
 P0181 P0182 P0183 Fuel tank temperature sensor
 P0327 P0328 Knock sensor
 P0335 Crankshaft position sensor (POS)
 P0340 P0345 Camshaft position sensor (PHASE)
 P0460 P0461 P0462 P0463 Fuel level sensor
 P0500 Vehicle speed sensor
 P0605 ECM
 P0643 Sensor power supply
 P0700 TCM
 P0705 Park/neutral position (PNP) switch
 P0850 Park/neutral position (PNP) switch
 P1610 - P1615 NATS
 P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2  P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater  P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
 P0075 P0081 Intake valve timing control solenoid valve
 P0130 P0131 P0132 P0133 P0150 P0151 P0152 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
 P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
 P0441 EVAP control system purge flow monitoring
 P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
 P0447 P0448 EVAP canister vent control valve
 P0451 P0452 P0453 EVAP control system pressure sensor
 P0550 Power steering pressure sensor
 P0603 ECM power supply
 P0710 P0717 P0720 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767
P1772 P1774 A/T related sensors, solenoid valves and switches
 P1217 Engine over temperature (OVERHEAT)
 P1805 Brake switch
 P2100 P2103 P2118 Electric throttle control actuator
 P2101 Electric throttle control function
3  P0011 P0021 Intake valve timing control  P0171 P0172 P0174 P0175 Fuel injection system function
 P0300 - P0306 Misfire
 P0420 P0430 Three way catalyst function
 P0442 EVAP control system (SMALL LEAK)
 P0455 EVAP control system (GROSS LEAK)
 P0456 EVAP control sys tem (VERY SMALL LEAK)
 P0506 P0507 Idle speed control system
 P1148 P1168 Closed loop control
 P1211 TCS control unit
 P1212 TCS communication line
 P1421 COLD START CONTROL
 P1564 ICC steering switch/ASCD steering switch
 P1568 ICC command valve*
 P1572 ICC brake switch/ASCD brake switch
 P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor
 P1715 Turbine revolution sensor
 P2119 Electric throttle control actuator
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DTC P1421 COLD START CONTROLEC-451
< SERVICE INFORMATION > [VQ35DE]
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DTC P1421 COLD START CONTROL
DescriptionINFOID:0000000001326309
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way ca
talyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicINFOID:0000000001326310
DTC Confirmation ProcedureINFOID:0000000001326311
NOTE:
 If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
 If DTC P1421 is displayed with other DTC, firs t perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that the “COOLAN TEMP/S” indication is between 4°C (39 °F) and 36 °C (97 °F).
If “COOLAN TEMP/S” indication is within the specified value, go to the following step.
If “COOLANT TEMP/S” indication is out of the specified value, cool engine down or warm engine up and
go to step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-451, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001326312
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-85, "
Idle Air Volume Learning".
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 2.
No >> Follow the instruction of Idle Air Volume Learning.
2.CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.
 Crushed intake air passage
 Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
3.CHECK FUEL INJECTION SYSTEM FUNCTION
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421 Cold start emission reduction
strategy monitoring ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.  Lack of intake air volume
 Fuel injection system
ECM
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TROUBLE DIAGNOSISEC-671
< SERVICE INFORMATION > [VK45DE]
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Fail-Safe ChartINFOID:0000000001326525
When the DTC listed below is detected, the EC
M enters fail-safe mode and the MIL lights up.
Priority Detected items (DTC)
1  U1000 U1001 CAN communication line  U1010 CAN communication
 P0101 P0102 P0103 Mass air flow sensor
 P0112 P0113 P0127 Intake air temperature sensor
 P0117 P0118 P0125 Engine coolant temperature sensor
 P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
 P0128 Thermostat function
 P0181 P0182 P0183 Fuel tank temperature sensor
 P0327 P0328 P0332 P0333 Knock sensor
 P0335 Crankshaft position sensor (POS)
 P0340 Camshaft posi tion sensor (PHASE)
 P0460 P0461 P0462 P0463 Fuel level sensor
 P0500 Vehicle speed sensor
 P0605 ECM
 P0643 Sensor power supply
 P0700 TCM
 P0705 Park/neutral position (PNP) switch
 P0850 Park/neutral position (PNP) switch
 P1610 - P1615 NATS
 P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2  P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater  P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
 P0075 P0081 Intake valve timing control solenoid valve
 P0130 P0131 P0132 P0133 P0150 P0151 P0152 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
 P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
 P0441 EVAP control system purge flow monitoring
 P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
 P0447 P0448 EVAP canister vent control valve
 P0451 P0452 P0453 EVAP control system pressure sensor
 P0550 Power steering pressure sensor
 P0603 ECM power supply
 P0710 P0717 P0720 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767
P1772 P1774 A/T related sensors, solenoid valves and switches
 P1140 P1145 Intake valve timing control position sensor
 P1217 Engine over temperature (OVERHEAT)
 P1805 Brake switch
 P2100 P2103 Throttle control motor relay
 P2101 Electric throttle control function
 P2118 Throttle control motor
3  P0011 P0021 Intake valve timing control  P0171 P0172 P0174 P0175 Fuel injection system function
 P0300 - P0308 Misfire
 P0420 P0430 Three way catalyst function
 P0442 P0456 EVAP co ntrol system (SMALL LEAK, VERY SMALL LEAK)
 P0455 EVAP control system (GROSS LEAK)
 P0506 P0507 Idle speed control system
 P1148 P1168 Closed loop control
 P1211 TCS control unit
 P1212 TCS communication line
 P1421 Cold start control
 P1564 ICC steering switch / ASCD steering switch
 P1568 ICC command value
 P1572 ICC brake switch / ASCD brake switch
 P1574 ICC vehicle speed sensor / ASCD vehicle speed sensor
 P1715 Turbine revolution sensor
 P1800 VIAS control solenoid valve
 P2119 Electric throttle control actuator
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DTC P1421 COLD START CONTROLEC-1045
< SERVICE INFORMATION > [VK45DE]
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DTC P1421 COLD START CONTROL
DescriptionINFOID:0000000001326914
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way ca
talyst by heating the catalyst and reduces emissions.
On Board Diagnosis LogicINFOID:0000000001326915
DTC Confirmation ProcedureINFOID:0000000001326916
NOTE:
 If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
 If DTC P1421 is displayed with other DTC, firs t perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that the “COOLAN TEMP/S” indication is between 4°C (39 °F) and 36 °C (97 °F).
If “COOLAN TEMP/S” indication is within the specified value, go to the following step.
If “COOLANT TEMP/S” indication is out of the specified value, cool engine down or warm engine up and
go to step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to EC-1045, "
Diagnosis Procedure".
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnosis ProcedureINFOID:0000000001326917
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-663, "
Idle Air Volume Learning".
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 2.
No >> Follow the instruction of Idle Air Volume Learning.
2.CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.
 Crushed intake air passage
 Intake air passage clogging
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning part
3.CHECK FUEL INJECTION SYSTEM FUNCTION
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421 Cold start emission reduction
strategy monitoring ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.  Lack of intake air volume
 Fuel injection system
ECM
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