Idle air INFINITI QX4 2001 Factory Owners Manual

Diagnostic ProcedureNBEC0274
1 INSPECTION START
With CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªSELF DIAG RESULTSº mode with CONSULT-II.
3. Touch ªERASEº.
4.Perform ªDTC Confirmation Procedureº.
See EC-444.
5. Is the 1st trip DTC P0605 displayed again?
With GST
1. Turn ignition switch ªONº.
2. Select MODE 4 with GST.
3. Touch ªERASEº.
4.Perform ªDTC Confirmation Procedureº.
See EC-444.
5. Is the 1st trip DTC P0605 displayed again?
YesorNo
Ye s©GO TO 2.
No©INSPECTION END
2 REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs. Refer to ªNVIS (NIS-
SAN VEHICLE IMMOBILIZER SYSTEM Ð NATS)º, EC-74.
3. Perform ªIdle Air Volume Learningº, EC-57,
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
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DTC P0605 ECM
Diagnostic Procedure
EC-445

DescriptionNBEC0523If DTC P1130 is displayed with P1165, first perform trouble diag-
nosis for DTC P1165, EC-493.
SYSTEM DESCRIPTIONNBEC0523S01
Sensor Input Signal to ECMECM func-
tionActuator
Throttle position sensor Throttle position
Swirl control
valve con-
trolSwirl control valve control sole-
noid valve
"Vacuum signal
Swirl control valve actuator
"
Swirl control valve Ignition switch Start signal
Crankshaft position sensor (POS) Engine speed (POS signal)
Crankshaft position sensor (REF) Engine speed (REF signal)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
This system has a swirl control valve in the intake passage of each
cylinder.
While idling and during low engine speed operation, the swirl con-
trol valve closes. Thus the velocity of the air in the intake passage
increases, promoting the vaporization of the fuel and producing a
swirl in the combustion chamber.
Because of this operation, this system tends to increase the burn-
ing speed of the gas mixture, improve fuel consumption, and
increase the stability in running conditions.
Also, except when idling and during low engine speed operation,
this system opens the swirl control valve. In this condition, this
system tends to increase power by improving intake efficiency via
reduction of intake flow resistance, intake flow.
The solenoid valve controls swirl control valve's shut/open condi-
tion. This solenoid valve is operated by the ECM.
Throttle position
sensor (Idle posi-
tion)Engine speedSwirl control valve
control solenoid
valveSwirl control valve
ON Below 3,200 rpm ON Closed
OFFLess than 3,200
rpmON Closed
More than 3,600
rpmOFF Open
When engine coolant temperature is below 10ÉC (50ÉF) and above 55ÉC (131ÉF),
swirl control valve is kept open regardless of above condition.
SEF446Z
DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Description
EC-458

PROCEDURE BNBEC0530S02
1 CHECK INTAKE SYSTEM
1. Start engine and let it idle.
2. Check intake air system for air leaks.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-
II)©GO TO 3.
NG©Repair intake system.
2 CHECK SWIRL CONTROL VALVE CONTROL SOLENOID VALVE CIRCUIT
With CONSULT-II
1. Select ªSWIRL CONT SOL VALVEº in ªACTIVE TESTº mode with CONSULT-II.
2. Touch ªONº and ªOFFº on CONSULT-II screen.
SEF003Z
3. Make sure that clicking sound is heard from the swirl control valve control solenoid valve.
OK or NG
OK©GO TO 6.
NG©GO TO 3.
DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-466

IEVAP purge line rubber tube bent.
IBlocked or bent rubber tube to EVAP control system pressure
sensor
ILoose or disconnected rubber tube
IEVAP canister vent control valve and the circuit
IEVAP canister purge volume control solenoid valve
IAbsolute pressure sensor
IFuel tank temperature sensor
IO-ring of EVAP canister vent control valve is missing or dam-
aged.
IWater separator
IEVAP canister is saturated with water.
IFuel level sensor and the circuit
IEVAP control system pressure sensor
SEF881X
SEF882X
SEF883X
DTC Confirmation ProcedureNBEC0317CAUTION:
Never remove fuel filler cap during the DTC confirmation pro-
cedure.
NOTE:
IIf DTC P1441 is displayed with P0440, perform TROUBLE
DIAGNOSIS FOR DTC P1441 first.
IIf ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PRO-
CEDUREº has been previously conducted, always turn
ignition switch ªOFFº and wait at least 5 seconds before
conducting the next test.
IAfter repair, make sure that the hoses and clips are
installed properly.
TESTING CONDITION:
IOpen engine hood before conducting following proce-
dure.
IIf any of following condition is met just before the DTC
confirmation procedure, leave the vehicle for more than 1
hour.
a)Fuel filler cap is removed.
b)Refilled or drained the fuel.
c)EVAP component parts is/are removed.
IBefore performing the following procedure, confirm that
battery voltage is more than 11V at idle.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Make sure the following conditions are met.
FUEL LEVEL SE: 1.08 - 0.2V
COOLAN TEMP/S: 0 - 32ÉC (32 - 90ÉF)
FUEL T/TMP SE: 0 - 35ÉC (32 - 95ÉF)
INT A/TEMP SE: More than 0ÉC (32ÉF)
If NG, turn ignition switch ªOFFº and leave the vehicle in a cool
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DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
Possible Cause (Cont'd)
EC-527

11 CHECK EVAP CANISTER
Weigh the EVAP canister with the EVAP canister vent control valve attached.
The weight should be less than 1.8 kg (4.0 lb).
OK or NG
OK (With CONSULT-II)©GO TO 13.
OK (Without CONSULT-
II)©GO TO 14.
NG©GO TO 12.
12 DETECT MALFUNCTIONING PART
Check the following.
IEVAP canister for damage
IEVAP hose between EVAP canister and water separator for clogging or poor connection
©Repair hose or replace EVAP canister.
13 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
With CONSULT-II
1. Disconnect vacuum hose to EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine.
3. Perform ªPURG VOL CONT/Vº in ªACTIVE TESTº mode.
4. Touch ªQuº on CONSULT-II screen to increase ªPURG VOL CONT/Vº opening to 100.0%.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
SEF984Y
OK or NG
OK©GO TO 16.
NG©GO TO 15.
14 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose to EVAP canister purge volume control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
Vacuum should exist.
OK or NG
OK©GO TO 17.
NG©GO TO 15.
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DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
Diagnostic Procedure (Cont'd)
EC-535

DescriptionNBEC0319SYSTEM DESCRIPTIONNBEC0319S01
Sensor Input Signal to ECMECM
functionActuator
Crankshaft position sensor (POS) Engine speed (POS signal)
EVAP can-
ister purge
flow controlEVAP canister purge volume
control solenoid valve Crankshaft position sensor (REF) Engine speed (REF signal)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle position
Throttle position switch Closed throttle position
Heated oxygen sensorsDensity of oxygen in exhaust gas
(Mixture ratio feedback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Vehicle speed sensor Vehicle speed
This system controls flow rate of fuel vapor from the EVAP canis-
ter. The opening of the vapor by-pass passage in the EVAP canis-
ter purge volume control solenoid valve changes to control the flow
rate. The EVAP canister purge volume control solenoid valve
repeats ON/OFF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engine control.
The optimum value stored in the ECM is determined by consider-
ing various engine conditions. When the engine is operating, the
flow rate of fuel vapor from the EVAP canister is regulated as the
air flow changes.
SEF337U
COMPONENT DESCRIPTIONNBEC0319S02The EVAP canister purge volume control solenoid valve uses a
ON/OFF duty to control the flow rate of fuel vapor from the EVAP
canister. The EVAP canister purge volume control solenoid valve
is moved by ON/OFF pulses from the ECM. The longer the ON
pulse, the greater the amount of fuel vapor that will flow through the
valve.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0320Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/VIEngine: After warming up
IAir conditioner switch ªOFFº
IShift lever: ªNº
INo-loadIdle (Vehicle stopped) 0%
2,000 rpm Ð
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DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Description
EC-541

SEF355X
Overall Function CheckNBEC0336Use this procedure to check the overall monitoring function of the
EVAP control system purge flow monitoring. During this check, a
1st trip DTC might not be confirmed.
WITH GSTNBEC0336S011) Lift up drive wheels.
2) Start engine (TCS switch ªOFFº) and warm it up to normal
operating temperature.
3) Turn ignition switch ªOFFº, wait at least 10 seconds.
4) Start engine and wait at least 70 seconds.
5) Set voltmeter probes to ECM terminals 84 (EVAP control sys-
tem pressure sensor signal) and ground.
6) Check EVAP control system pressure sensor value at idle
speed and note it.
7) Establish and maintain the following conditions for at least 1
minute.
Air conditioner switch ON
Steering wheel Fully turned
Headlamp switch ON
Rear window defogger switch ON
Engine speed Approx. 3,000 rpm
Gear position Any position other than ªPº, ªNº or ªRº
8) Verify that EVAP control system pressure sensor value stays
0.1V less than the value at idle speed (measured at step 6) for
at least 1 second.
9) If NG, go to ªDiagnostic Procedureº, EC-564.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Overall Function Check
EC-563

3 CHECK PURGE FLOW
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port and
install vacuum gauge.
SEF983Y
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum gauge indication when revving engine up to 2,000 rpm.
Vacuum should exist.
6. Release the accelerator pedal fully and let idle.
Vacuum should not exist.
OK or NG
OK©GO TO 7.
NG©GO TO 4.
4 CHECK EVAP PURGE LINE
1. Turn ignition switch ªOFFº.
2. Check EVAP purge line for improper connection or disconnection.
Refer to ªEVAPORATIVE EMISSION LINE DRAWINGº, EC-36.
OK or NG
OK (With CONSULT-II)©GO TO 5.
OK (Without CONSULT-
II)©GO TO 6.
NG©Repair it.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure (Cont'd)
EC-565

Component DescriptionNBEC0361The malfunction information related to A/T (Automatic Transmission) is transferred through the line (circuit)
from TCM (Transmission control module) to ECM. Therefore, be sure to erase the malfunction information such
as DTC not only in TCM (Transmission control module) but also ECM after the A/T related repair.
On Board Diagnosis LogicNBEC0363Malfunction is detected when an incorrect signal from TCM (Trans-
mission control module) is sent to ECM.
Possible CauseNBEC0594IHarness or connectors
[The communication line circuit between ECM and TCM
(Transmission control module) is open or shorted.]
IDead (Weak) battery
ITCM (Transmission control module)
SEF058Y
DTC Confirmation ProcedureNBEC0364NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V at idle.
WITH CONSULT-IINBEC0364S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait at least 40 seconds.
4) If 1st trip DTC is detected, go to ªDTC P0600 A/T COMMUNI-
CATION LINE Diagnostic Procedureº, EC-443.
WITH GSTNBEC0364S02Follow the procedure ªWITH CONSULT-IIº above.
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DTC P1605 A/T DIAGNOSIS COMMUNICATION LINE
Component Description
EC-603

DescriptionNBEC0596SYSTEM DESCRIPTIONNBEC0596S01
Sensor Input Signal to ECMECM func-
tionActuator
Mass air flow sensor Amount of intake air
VIAS con-
trolVIAS control solenoid valve Throttle position sensor Throttle position
Closed throttle position Throttle valve idle position
Ignition switch Start signal
Crankshaft position sensor (POS) Engine speed (POS signal)
Crankshaft position sensor (REF) Engine speed (REF signal)
Engine coolant temperature sensor Engine coolant temperature
SEF447Z
When the engine is running at low or medium speed, the power
valve is fully closed. Under this condition, the effective suction port
length is equivalent to the total length of the intake manifold collec-
tor's suction port including the intake valve. This long suction port
provides increased air intake which results in improved suction
efficiency and higher torque generation.
The surge tank and one-way valve are provided. When engine is
running at high speed, the ECM sends the signal to the VIAS con-
trol solenoid valve. This signal introduces the intake manifold
vacuum into the power valve actuator and therefore opens the
power valve to two suction passages together in the collector.
Under this condition, the effective port length is equivalent to the
length of the suction port provided independently for each cylinder.
This shortened port length results in enhanced engine output with
reduced suction resistance under high speeds.
VARIABLE INDUCTION AIR CONTROL SYSTEM (VIAS)
Description
EC-610