timing INFINITI QX4 2001 Factory Owner's Guide

SEF452Y
Idle Air Volume LearningNBEC0642
SEF454Y
SEF455Y
DESCRIPTIONNBEC0642S01ªIdle Air Volume Learningº is an operation to learn the idle air vol-
ume that keeps each engine within the specific range. It must be
performed under any of the following conditions:
IEach time IACV-AAC valve, throttle body or ECM is replaced.
IIdle speed or ignition timing is out of specification.
PRE-CONDITIONINGNBEC0642S02Before performing ªIdle Air Volume Learningº, make sure that all of
the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are
missed for even a moment.
IBattery voltage: More than 12.9V (At idle)
IEngine coolant temperature: 70 - 99ÉC (158 - 210ÉF)
IPNP switch: ON
IElectric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime running light systems, if
the parking brake is applied before the engine is started the
headlamp will not illuminate.
ICooling fan motor: Not operating
ISteering wheel: Neutral (Straight-ahead position)
IVehicle speed: Stopped
ITransmission: Warmed-up
For A/T models with CONSULT-II, drive vehicle until ªFLUID
TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
For A/T models without CONSULT-II, drive vehicle for 10 min-
utes.
OPERATION PROCEDURENBEC0642S03With CONSULT-IINBEC0642S03011. Turn ignition switch ªONº and wait at least 1 second.
2. Turn ignition switch ªOFFº and wait at least 10 seconds.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic ªPRE-CONDITION-
INGº (previously mentioned) are in good order.
5. Turn ignition switch ªOFFº and wait at least 10 seconds.
6. Start the engine and let it idle for at least 30 seconds.
7. Select ªIDLE AIR VOL LEARNº in ªWORK SUPPORTº mode.
8. Touch ªSTARTº and wait 20 seconds.
9. Make sure that ªCMPLTº is displayed on CONSULT-II screen.
If ªINCMPº is displayed, ªIdle Air Volume Learningº will not be
carried out successfully. In this case, find the cause of the
problem by referring to the NOTE below.
10. Rev up the engine two or three times. Make sure that idle
speed and ignition timing are within specifications.
ITEM SPECIFICATION
Idle speed 750±50 rpm (in ªPº or ªNº position)
Ignition timing 15ɱ5É BTDC (in ªPº or ªNº position)
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BASIC SERVICE PROCEDURE
Idle Air Volume Learning
EC-57

SEF944Y
Without CONSULT-IINBEC0642S03021. Turn ignition switch ªONº and wait at least 1 second.
2. Turn ignition switch ªOFFº and wait at least 10 seconds.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic ªPRE-CONDITION-
INGº (previously mentioned) are in good order.
5. Turn ignition switch ªOFFº and wait at least 10 seconds.
6. Start the engine and let it idle for at least 30 seconds.
7. Disconnect throttle position sensor harness connector (brown),
then reconnect it within 5 seconds.
8. Wait 20 seconds.
9. Make sure that idle speed is within specifications. If not, the
result will be incomplete. In this case, find the cause of the
problem by referring to the NOTE below.
10. Rev up the engine two or three times. Make sure that idle
speed and ignition timing are within specifications.
ITEM SPECIFICATION
Idle speed 750±50 rpm (in ªPº or ªNº position)
Ignition timing 15ɱ5É BTDC (in ªPº or ªNº position)
NOTE:
If idle air volume learning cannot be performed successfully,
proceed as follows:
1)Check that throttle valve is fully closed.
2)Check PCV valve operation.
3)Check that downstream of throttle valve is free from air
leakage.
4)Adjust closed throttle position switch and reset memory.
(Refer to Basic Inspection, EC-101.)
5)When the above four items check out OK, engine compo-
nent parts and their installation condition are question-
able. Check and eliminate the cause of the problem.
It is useful to perform ªTROUBLE DIAGNOSIS Ð SPECIFI-
CATION VALUEº, EC-136.
6)If any of the following conditions occur after the engine
has started, eliminate the cause of the problem and per-
form ªIdle air volume learningº all over again:
IEngine stalls.
IErroneous idle.
IBlown fuses related to the IACV-AAC valve system.
BASIC SERVICE PROCEDURE
Idle Air Volume Learning (Cont'd)
EC-58

SRT Set Timing=NBEC0031S0311SRT is set as ªCMPLTº after self-diagnosis has been performed one or more times. Completion of SRT is done
regardless of whether the result is OK or NG. The set timing is different between OK and NG results and is
shown in the table below.
Self-diagnosis resultExample
DiagnosisIgnition cycle
+ON,OFF+ON,OFF+ON,OFF+ON,
All OK Case 1 P0400 OK (1) Ð (1) OK (2) Ð (2)
P0402 OK (1) Ð (1) Ð (1) OK (2)
P1402 OK (1) OK (2) Ð (2) Ð (2)
SRT of EGR ªCMPLTº ªCMPLTº ªCMPLTº ªCMPLTº
Case 2 P0400 OK (1) Ð (1) Ð (1) Ð (1)
P0402 Ð (0) Ð (0) OK (1) Ð (1)
P1402 OK (1) OK (2) Ð (2) Ð (2)
SRT of EGR ªINCMPº ªINCMPº ªCMPLTº ªCMPLTº
NG exists Case 3 P0400 OK OK Ð Ð
P0402 Ð Ð Ð Ð
P1402 NG Ð NGNG
(Consecutive NG)
(1st trip)
DTC1st trip DTC Ð 1st trip DTCDTC
(= MIL ªONº)
SRT of EGR ªINCMPº ªINCMPº ªINCMPº ªCMPLTº
OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
Ð: Self-diagnosis is not carried out.
When all SRT related self-diagnoses showed OK results in a single cycle (Ignition OFF-ON-OFF), the SRT
will indicate ªCMPLTº.,Case 1 above
When all SRT related self-diagnoses showed OK results through several different cycles, the SRT will indi-
cate ªCMPLTº at the time the respective self-diagnoses have at least one OK result.,Case 2 above
If one or more SRT related self-diagnoses showed NG results in 2 consecutive cycles, the SRT will also indi-
cate ªCMPLTº.,Case 3 above
The table above shows that the minimum number of cycles for setting SRT as ªINCMPº is one (1) for each
self-diagnosis (Case1&2)ortwo(2)foroneofself-diagnoses (Case 3). However, in preparation for the state
emissions inspection, it is unnecessary of each self-diagnosis to be executed twice (Case 3) for the following
reasons:
IThe SRT will indicate ªCMPLTº at the time the respective self-diagnoses have one (1) OK result.
IThe emissions inspection requires ªCMPLTº of the SRT only with OK self-diagnosis results.
IWhen, during SRT driving pattern, 1st trip DTC (NG) is detected prior to ªCMPLTº of SRT, the self-diag-
nosis memory must be erased from ECM after repair.
IIf the 1st trip DTC is erased, all the SRT will indicate ªINCMPº.
NOTE:
SRT can be set as ªCMPLTº together with the DTC(s). Therefore, DTC check must always be carried out prior
to the state emission inspection even though the SRT indicates ªCMPLTº.
SRT Service ProcedureNBEC0031S0312If a vehicle has failed the state emissions inspection due to one or more SRT items indicating ªINCMPº, review
the flowchart diagnostic sequence on the next page.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Emission-related Diagnostic Information (Cont'd)
EC-63

Items Fuel Injection System Misfire Other
1st Trip Freeze Frame Data
(clear)*1, *2 *1, *2 1 (pattern B)
For details about patterns ªBº and ªCº under ªFuel Injection Systemº and ªMisfireº, see EC-78.
For details about patterns ªAº and ªBº under ªOtherº, see EC-80.
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
OBD System Operation Chart (Cont'd)
EC-76

ENGINE CONTROL COMPONENT PARTS/CONTROL
SYSTEMS APPLICATION
NBEC0034S02
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOSTIC
RESULTS
D ATA
MONI-
TORD ATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor
(POS)XXXX
Crankshaft position sensor (REF) X X X
Mass air flow sensor X X X
Engine coolant temperature sen-
sorXXXXX
Heated oxygen sensor 1 (front) X X X X X
Heated oxygen sensor 2 (rear) X X X X X
Vehicle speed sensorXXXX
Throttle position sensor X X X
Fuel tank temperature sensor X X X X
EVAP control system pressure
sensorXXX
Absolute pressure sensor X X X
Intake air temperature sensor X X X
Knock sensor X
Ignition switch (start signal) X X
Closed throttle position switch X X X
Closed throttle position switch
(throttle position sensor signal)XX
Air conditioner switch X X
Park/neutral position (PNP)
switchXXX
Power steering oil pressure
switchXX
Battery voltage X X
Ambient air temperature switch X X
Load signal X X
Swirl control valve control
vacuum check switchXXX
Fuel level sensor X X X
Intake valve timing control posi-
tion sensorXXX
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-82

ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOSTIC
RESULTS
D ATA
MONI-
TORD ATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Injectors X X X
Power transistor (Ignition timing)X
(Ignition
signal)XXX
IACV-AAC valve X X X X
EVAP canister purge volume
control solenoid valveX XXX X
Air conditioner relay X X
Fuel pump relay X X X X
Heated oxygen sensor 1 (front)
heaterXXXX
Heated oxygen sensor 2 (rear)
heaterXXXX
EVAP canister vent control valve X X X X
Vacuum cut valve bypass valve X X X X X
Swirl control valve control sole-
noid valveX XXX
VIAS control solenoid valve X X X
Intake valve timing control sole-
noid valveX XXX
Calculated load value X X X
X: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-60.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-83

WORK SUPPORT MODE=NBEC0034S04
WORK ITEM CONDITION USAGE
TP SW/TP SEN IDLE POSI ADJIFOLLOW THE BASIC INSPECTION INSTRUCTION IN
THE SERVICE MANUAL.When adjusting the idle throttle
position
FUEL PRESSURE RELEASEIFUEL PUMP WILL STOP BY TOUCHING ªSTARTº
DURING IDLING.
CRANK A FEW TIMES AFTER ENGINE STALLS.When releasing fuel pressure
from fuel line
IDLE AIR VOL LEARNITHE IDLE AIR VOLUME THAT KEEPS THE ENGINE
WITHIN THE SPECIFIED RANGE IS MEMORIZED IN
ECM.When learning the idle air volume
SELF-LEARNING CONTITHE COEFFICIENT OF SELF-LEARNING CONTROL
MIXTURE RATIO RETURNS TO THE ORIGINAL
COEFFICIENT.When clearing the coefficient of
self-learning control valve
EVAP SYSTEM CLOSE OPEN THE VACUUM CUT VALVE BYPASS VALVE AND
CLOSE THE EVAP CANISTER VENT CONTROL VALVE
IN ORDER TO MAKE EVAP SYSTEM CLOSE UNDER
THE FOLLOWING CONDITIONS.
IIGN SW ªONº
IENGINE NOT RUNNING
IAMBIENT TEMPERATURE IS ABOVE 0ÉC (32ÉF).
INO VACUUM AND NO HIGH PRESSURE IN EVAP
SYSTEM
ITANK FUEL TEMP. IS MORE THAN 0ÉC (32ÉF).
IWITHIN 10 MINUTES AFTER STARTING ªEVAP SYS-
TEM CLOSEº
IWHEN TRYING TO EXECUTE ªEVAP SYSTEM
CLOSEº UNDER THE CONDITION EXCEPT ABOVE,
CONSULT-II WILL DISCONTINUE IT AND DISPLAY
APPROPRIATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-II MAY DIS-
PLAY ªBATTERY VOLTAGE IS LOW. CHARGE
BATTERYº, EVEN IN USING CHARGED BATTERY.When detecting EVAP vapor leak
point of EVAP system
TARGET IGNITION TIMING ADJ*IIDLE CONDITIONIWhen adjusting target ignition
timing
After adjustment, confirm target
ignition timing with a timing
light.
IIf once the ªTARGET IDLE
RPM ADJº has been done, the
Idle Air Volume Learning proce-
dure will not be completed.
TARGET IDLE RPM ADJ*IIDLE CONDITION When setting target idle speed
*: This function is not necessary in the usual service procedure.
SELF-DIAGNOSTIC MODENBEC0034S05DTC and 1st Trip DTCNBEC0034S0501Regarding items of ªDTC and 1st trip DTCº, refer to ªTROUBLE
DIAGNOSIS Ð INDEXº (See EC-8.)
Freeze Frame Data and 1st Trip Freeze Frame DataNBEC0034S0502
Freeze frame data
item*1Description
DIAG TROUBLE
CODE
[PXXXX]IThe engine control component part/control system has a trouble code, it is displayed as ªPXXXXº.
(Refer to ªTROUBLE DIAGNOSIS Ð INDEXº, EC-8.)
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-85

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
IGN TIMING [BTDC]qIIndicates the ignition timing computed
by ECM according to the input signals.IWhen the engine is stopped, a certain
value is indicated.
IACV-AAC/V [step]qIIndicates the IACV-AAC valve control
value computed by ECM according to
the input signals.
PURG VOL C/V [%]IIndicates the EVAP canister purge vol-
ume control solenoid valve control
value computed by the ECM according
to the input signals.
IThe opening becomes larger as the
value increases.
A/F ALPHA-B1 [%]q
IThe mean value of the air-fuel ratio
feedback correction factor per cycle is
indicated.IWhen the engine is stopped, a certain
value is indicated.
IThis data also includes the data for the
air-fuel ratio learning control. A/F ALPHA-B2 [%]q
AIR COND RLY
[ON/OFF]qIThe air conditioner relay control condi-
tion (determined by ECM according to
the input signal) is indicated.
FUEL PUMP RLY
[ON/OFF]qIIndicates the fuel pump relay control
condition determined by ECM accord-
ing to the input signals.
VENT CONT/V
[ON/OFF]IThe control condition of the EVAP can-
ister vent control valve (determined by
ECM according to the input signal) is
indicated.
ION ... Closed
OFF ... Open
HO2S1 HTR (B1)
[ON/OFF]IIndicates [ON/OFF] condition of front
heated oxygen sensor heater deter-
mined by ECM according to the input
signals. HO2S1 HTR (B2)
[ON/OFF]
HO2S2 HTR (B1)
[ON/OFF]IIndicates [ON/OFF] condition of rear
heated oxygen sensor heater deter-
mined by ECM according to the input
signals. HO2S2 HTR (B2)
[ON/OFF]
VC/V BYPASS/V
[ON/OFF]IThe control condition of the vacuum cut
valve bypass valve (determined by
ECM according to the input signal) is
indicated.
ION ... Open
OFF ... Closed
CAL/LD VALUE [%]IªCalculated load valueº indicates the
value of the current airflow divided by
peak airflow.
ABSOL TH´P/S [%]IªAbsolute throttle position sensorº indi-
cates the throttle opening computed by
ECM according to the signal voltage of
the throttle position sensor.
MASS AIRFLOW
[g´m/s]IIndicates the mass airflow computed by
ECM according to the signal voltage of
the mass airflow sensor.GI
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-89

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
INT/V TIM (B1) [ÉCA]
IIndicate [ÉCA] of intake camshaft
advanced angle.
INT/V TIM (B2) [ÉCA]
INT/V SOL (B1) [%]IThe control condition of the intake
valve timing control solenoid valve is
indicated. INT/V SOL (B2) [%]
TRVL AFTER MIL
[km] or [Mile]IDistance traveled while MIL is activated
VIAS S/V
[ON/OFF]IThe control condition of the VIAS con-
trol solenoid valve (determined by ECM
according to the input signal) is indi-
cated.
IOFF ... VIAS control solenoid valve is
not operating.
ON ... VIAS control solenoid valve is
operating.
SWL CON VC SWIIndicates [ON/OFF] condition from the
swirl control valve control vacuum
check switch.
ON ... Swirl control valve is not opera-
tional.
OFF ... Swirl control valve is opera-
tional.
IDL A/V LEANIDisplay the condition of idle air volume
learning
YET ... Idle air volume learning has not
been performed yet.
CMPLT ... Idle air volume learning has
already been performed successfully.
INCMP ... Idle air volume learning has
not been performed successfully.
Voltage [V]IVoltage measured by the voltage
probe.
Frequency
[msec] or [Hz] or [%]IPulse width, frequency or duty cycle
measured by the pulse probe.IOnly ª#º is displayed if item is unable to
be measured.
IFigures with ª#ºs are temporary ones.
They are the same figures as an actual
piece of data which was just previously
measured.
NOTE:
IAny monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
IRegarding R50 model, ª-B1º indicates right bank and ª-B2º indicates left bank.
IBank 1 (-B1 or BK1) includes No. 1 cylinder.
DATA MONITOR (SPEC) MODENBEC0034S11
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
MAS A/F SE-B1 [V]qqIThe signal voltage of the mass air flow sen-
sor specification is displayed.IWhen the engine is running, specifi-
cation range is indicated.
B/FUEL SCHDL
[msec]IªBase fuel scheduleº indicates the fuel injec-
tion pulse width programmed into ECM,
prior to any learned on board correction.IWhen the engine is running, specifi-
cation range is indicated.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-90

Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
A/F ALPHA-B1 [%]q
IIndicates the mean value of the air-fuel ratio
feedback correction factor per cycle.IWhen the engine is running, specifi-
cation range is indicated.
IThis data also includes the data for
the air-fuel ratio learning control. A/F ALPHA-B2 [%]q
NOTE:
IAny monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
IRegarding R50 model, ªB1º indicates bank 1 and ªB2º indicates bank 2.
ACTIVE TEST MODENBEC0034S07
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJECTIONIEngine: Return to the original
trouble condition
IChange the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.IHarness and connector
IFuel injectors
IHeated oxygen sensor
IGNITION TIMINGIEngine: Return to the original
trouble condition
ITiming light: Set
IRetard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.IAdjust initial ignition timing
IACV-AAC/V
OPENINGIEngine: After warming up, idle
the engine.
IChange the IACV-AAC valve
opening percent using CON-
SULT-II.Engine speed changes according
to the opening percent.IHarness and connector
IIACV-AAC valve
POWER BAL-
ANCEIEngine: After warming up, idle
the engine.
IA/C switch ªOFFº
IShift lever ªNº
ICut off each injector signal one
at a time using CONSULT-II.Engine runs rough or dies.IHarness and connector
ICompression
IInjectors
IPower transistor
ISpark plugs
IIgnition coils
ENG COOLANT
TEMPIEngine: Return to the original
trouble condition
IChange the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.IHarness and connector
IEngine coolant temperature sen-
sor
IFuel injectors
FUEL PUMP
RELAYIIgnition switch: ON
(Engine stopped)
ITurn the fuel pump relay ªONº
and ªOFFº using CONSULT-II
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.IHarness and connector
IFuel pump relay
VIAS SOL VALVEIIgnition switch: ON
ITurn solenoid valve ªONº and
ªOFFº with CONSULT-II and lis-
ten for operating sound.Solenoid valve makes an operating
sound.IHarness and connector
ISolenoid valve
SWIRL CONT
S O L VA LV EIIgnition switch: ON
ITurn solenoid valve ªONº and
ªOFFº with CONSULT-II and lis-
ten for operating sound.Solenoid valve makes an operating
sound.IHarness and connector
ISolenoid valve
PURG VOL
CONT/VIEngine: After warming up, run
engine at 1,500 rpm.
IChange the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II.Engine speed changes according
to the opening percent.IHarness and connector
ISolenoid valve
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
CONSULT-II (Cont'd)
EC-91