INFINITI QX4 2001 Factory Service Manual

12 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-I
With CONSULT-II
1. Loosen throttle position sensor fixing bolts.
2. Confirm that proper vacuum is applied. Refer to test No. 10. During adjustment, vacuum should be applied.
3. Insert 0.05 mm (0.0020 in) feeler gauge between stopper and throttle drum as shown in the figure.
SEF953Y
4. Turn throttle position sensor body counterclockwise until ªCLSD THL/P SWº signal switches to ªOFFº.
SEF954Y
SEF007Z
©GO TO 13.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-106

13 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-II
With CONSULT-II
1. Temporarily tighten sensor body fixing bolts as follows.
IGradually move the sensor body clockwise and stop it when ªCLSD THL/P SWº signal switches from ªOFFº to
ªONº, then temporarily tighten sensor body fixing bolts.
SEF954Y
2. Make sure two or three times that the signal is ªONº when the throttle valve is closed and ªOFFº when it is opened.
3. Remove 0.05 mm (0.0020 in) feeler gauge then insert 0.15 mm (0.0059 in) feeler gauge.
4. Make sure two or three times that the signal remains ªOFFº when the throttle valve is closed.
5. Tighten throttle position sensor.
6. Check the ªCLSD THL/P SWº signal again.
The signal remains ªOFFº while closing throttle valve.
OK or NG
OK©GO TO 14.
NG©GO TO 12.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-107

14 RESET THROTTLE POSITION SENSOR IDLE POSITION MEMORY
With CONSULT-II
NOTE:
Always warm up engine to normal operating temperature. If engine is cool, the throttle position sensor idle posi-
tion memory will not be reset correctly.
1. Confirm that proper vacuum is applied. Refer to Test No. 10.
2. Attach blind cap to vacuum port from which vacuum hose to throttle opener was disconnected.
3. Start engine.
4. Warm up engine to normal operating temperature.
5. Select ªTP SW/TP SEN IDLE POSI ADJº in ªWORK SUPPORTº mode.
6. Stop engine. (Turn ignition switch ªOFFº.)
7. Turn ignition switch ªONº and wait at least 5 seconds.
SEF864V
8. Turn ignition switch ªOFFº and wait at least 10 seconds.
9. Repeat steps 7 and 8 until ªCLSD THL POSº signal changes to ªONº.
SEF987Y
©GO TO 19.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-108

15 CHECK THROTTLE POSITION SWITCH CLOSED POSITION-II
1. Disconnect closed throttle position switch harness connector.
2. Check continuity between closed throttle position switch terminals6and5under the following conditions.
SEF330Z
IInsert the 0.05 mm (0.0020 in) and 0.15 mm (0.0059 in) feeler gauge alternately between the stopper and throttle drum
as shown in the figure.
SEF953Y
ªContinuity should existº while inserting 0.05 mm (0.0020 in) feeler gauge.
ªContinuity should not existº while inserting 0.15 mm (0.0059 in) feeler gauge.
OK or NG
OK©GO TO 18.
NG©GO TO 16.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-109

16 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-I
1. Loosen throttle position sensor fixing bolts.
2. Confirm that proper vacuum is applied. Refer to Test No. 10. During adjustment, vacuum should be applied.
3. Insert 0.05 mm (0.0020 in) feeler gauge between stopper and throttle drum as shown in the figure.
SEF953Y
SEF330Z
4. Turn throttle position sensor body counterclockwise until continuity does not exist.
SEF954Y
©GO TO 17.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-110

17 ADJUSTMENT THROTTLE POSITION SWITCH CLOSED POSITION-II
1. Temporarily tighten sensor body fixing bolts as follows.
IGradually move the sensor body clockwise and stop it when the continuity comes to exist, then temporarily
tighten sensor body fixing bolts.
SEF954Y
2. Make sure two or three times that the continuity exists when the throttle valve is closed and continuity does not exist
when it is opened.
3. Remove 0.05 mm (0.0020 in) feeler gauge then insert 0.15 mm (0.0059 in) feeler gauge.
4. Make sure two or three times that the continuity does not exist when the throttle valve is closed.
5. Tighten throttle position sensor.
6. Check the continuity again.
Continuity does not exist while closing the throttle valve.
OK or NG
OK©GO TO 18.
NG©GO TO 16.
18 RESET THROTTLE POSITION SENSOR IDLE POSITION MEMORY
NOTE:
Always warm up engine to normal operating temperature. If engine is cool, the throttle position sensor idle posi-
tion memory will not be reset correctly.
1. Confirm that proper vacuum is applied. Refer to Test No. 10.
2. Attach blind cap to vacuum port from which vacuum hose to throttle opener was disconnected.
3. Start engine.
4. Warm up engine to normal operating temperature.
5. Stop engine. (Turn ignition switch ªOFFº.)
6. Turn ignition switch ªONº and wait at least 5 seconds.
SEF864V
7. Turn ignition switch ªOFFº and wait at least 10 seconds.
8. Repeat steps 6 and 7, 20 times.
©GO TO 19.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-111

19 CHECK (1ST TRIP) DTC
1. Turn ignition switch ªOFFº.
2. Release vacuum from throttle opener.
3. Remove vacuum pump and vacuum hose from throttle opener.
4. Reinstall original vacuum hose to throttle opener securely.
5. Start engine and warm it up to normal operating temperature.
6. Rev (2,000 to 3,000 rpm) two or three times.
7. Make sure no (1st trip) DTC is displayed with CONSULT-II or GST.
OK or NG
OK©GO TO 21.
NG©GO TO 20.
20 REPAIR MALFUNCTION
Repair or replace components as necessary according to corresponding ªDiagnostic Procedureº.
©GO TO 19.
21 CHECK TARGET IDLE SPEED
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 30.
NG©GO TO 22.
22 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 23.
INCMP©1. Follow the construction of ªIdle Air Volume Leaningº.
2. GO TO 22.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-112

23 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 28.
NG©GO TO 24.
24 REPLACE IACV-AAC VALVE
Replace IACV-AAC valve.
©GO TO 25.
25 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 26.
INCMP©1. Follow the construction of ªIdle Air Volume Learningº.
2. GO TO 22.
26 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 28.
NG©GO TO 27.
27 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of a problem, but this is rarely
the case.)
2. Perform initialization of IVIS (NATS) system and registration of IVIS (NATS) ignition key IDs. Refer to ªIVIS (INFINITI
VEHICLE IMMOBILIZER SYSTEM Ð NATS)º, EC-74.
©GO TO 22.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-113

28 CHECK IGNITION TIMING
1. Start engine and warm it up to normal operating temperature.
2. Check ignition timing at idle using a timing light.
SEF572X
Ignition timing:
15ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 36.
NG©GO TO 29.
29 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-29, ªInstallationº.
OK or NG
OK©GO TO 27.
NG©1. Repair the timing chain installation.
2. GO TO 22.
30 CHECK IGNITION TIMING
1. Start engine and let it idle.
2. Check ignition timing at idle using a timing light.
SEF572X
Ignition timing:
15ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 36.
NG©GO TO 31.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-114

31 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-57.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 32.
INCMP©1. Follow the construction of ªIdle Air volume Learningº.
2. GO TO 31.
32 CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select ªENG SPEEDº in ªDATA MONITORº mode with CONSULT-II.
3. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
750±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 34.
NG©GO TO 33.
33 CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function.
(ECM may be the cause of a problem, but this is rarely the case.)
2. Perform initialization of NVIS (NATS) system and registration of NVIS (NATS) ignition key IDs. Refer to ªNVIS (NISSAN
VEHICLE IMMOBILIZER SYSTEM Ð NATS)º, EC-74.
©GO TO 31.
34 CHECK IGNITION TIMING AGAIN
Check ignition timing again. Refer to Test No. 30.
OK or NG
OK©GO TO 36.
NG©GO TO 35.
35 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-29, ªInstallationº.
OK or NG
OK©GO TO 33.
NG©1. Repair the timing chain installation.
2. GO TO 31.
36 ERASE UNNECESSARY DTC
After this inspection, unnecessary DTC No. might be displayed.
Erase the stored memory in ECM and TCM (Transmission control module).
Refer to ªHow to Erase Emission-Related Diagnostic Informationº, EC-72 and AT-35, ªHOW TO ERASE DTCº.
©INSPECTION END
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Basic Inspection (Cont'd)
EC-115