Page 837 of 2898

27 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.
M/T: 700±50 rpm
A/T: 800±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.
M/T: 700±50 rpm
A/T: 800±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 29.
NG©GO TO 28.
28 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 NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-74.
©GO TO 22.
29 CHECK IGNITION TIMING
1. Start engine and warm it up to normal operating temperature.
2. Check ignition timing at idle using a timing light.
SEF984U
Ignition timing:
M/T 8ɱ5É BTDC
A/T 10ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 37.
NG©GO TO 30.
30 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-28, ªInstallationº.
OK or NG
OK©GO TO 28.
NG©1. Repair the timing chain installation.
2. GO TO 22.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-113
Page 838 of 2898

31 CHECK IGNITION TIMING
1. Start engine and let it idle.
2. Check ignition timing at idle using a timing light.
SEF984U
Ignition timing:
M/T 8ɱ5É BTDC
A/T 10ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 37.
NG©GO TO 22.
32 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 33.
INCMP©1. Follow the construction of ªIdle Air volume Learningº.
2. GO TO 32.
33 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.
M/T: 700±50 rpm
A/T: 800±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.
M/T: 700±50 rpm
A/T: 800±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 35.
NG©GO TO 34.
34 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 NATS system and registration of NATS ignition key IDs. Refer to ªNATS (Nissan Anti-Theft
System)º, EC-74.
©GO TO 32.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-114
Page 840 of 2898
MODELS WITHOUT THROTTLE POSITION SWITCH=NJEC1736S02
1 INSPECTION START
1. Check service records for any recent repairs that may indicate a related problem, or a current need for scheduled
maintenance.
2. Open engine hood and check the following:
+Harness connectors for improper connections
+Vacuum hoses for splits, kinks and improper connections
+Wiring for improper connections, pinches and cuts
+Air cleaner clogging
+Hoses and ducts for leaks
SEF983U
©GO TO 2.
2 CHECK THROTTLE OPENER OPERATION-I
Confirm that there is a clearance between throttle drum and stopper.
SEF850Y
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 CHECK THROTTLE OPENER FIXING BOLTS
Check throttle opener fixing bolts for loosening.
OK or NG
OK©1. Repair or replace throttle body assembly.
2. GO TO 2.
NG©1. Retighten the fixing bolts.
2. GO TO 2.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-116
Page 841 of 2898
4 CHECK THROTTLE OPENER OPERATION-II
1. Start engine and let it idle.
2. Confirm that throttle opener rod moves backward and there is a clearance between throttle drum and throttle opener
rod.
SEF850Y
OK or NG
OK©GO TO 7.
NG©GO TO 5.
5 CHECK VACUUM SOURCE FOR THROTTLE OPENER
1. Disconnect vacuum hose connected to throttle opener.
2. Check vacuum existance with engine running.
SEF155Y
OK or NG
OK©1. Repair or replace throttle body assembly.
2. GO TO 2.
NG©GO TO 6.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-117
Page 842 of 2898
6 CHECK VACUUM HOSE
1. Stop engine.
2. Remove the vacuum hose.
3. Check the vacuum hose for splits, kinks and clogging.
SEF109L
OK or NG
OK©1. Clean vacuum port by blowing air.
2. GO TO 4.
NG©1. Replace vacuum hose.
2. GO TO 4.
7 CHECK THROTTLE DRUM OPERATION
Confirm that throttle drum moves to contact the stopper.
SEF850Y
OK or NG
OK©GO TO 10.
NG©GO TO 8.
8 CHECK ACCELERATOR WIRE INSTALLATION
1. Stop engine.
2. Check accelerator wire for slack.
OK or NG
OK©GO TO 9.
NG©1. Adjust accelerator wire. Refer to FE-3, ªAdjusting Accelerator Wireº.
2. GO TO 7.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-118
Page 843 of 2898
9 CHECK THROTTLE VALVE OPERATION
1. Remove intake air ducts.
2. Check throttle valve operation when moving throttle drum by hand.
OK or NG
OK©1. Retighten the throttle drum fixing nuts.
2. GO TO 7.
NG©1. Clean the throttle body and throttle valve.
2. GO TO 7.
10 CHECK THROTTLE POSITION SENSOR CLOSED POSITION-I
NOTE:
Always check ignition timing before performing the following.
1. Warm up engine to normal operating temperature.
2. Stop engine.
3. Remove the vacuum hose connected to the throttle opener.
4. Connect suitable vacuum hose to vacuum pump as shown below.
SEF793WA
5. Apply vacuum [more than þ40.0 kPa (±400 mbar, þ300 mmHg, þ11.81 inHg)] until the throttle drum is free from the
throttle opener rod.
Models with CONSULT-II©GO TO 11.
Models without CON-
SULT-II©GO TO 15.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-119
Page 844 of 2898

11 CHECK THROTTLE POSITION SENSOR CLOSED POSITION-II
With CONSULT-II
1. Connect ªCONSULT-IIº to the data link connector and select ªENGINEº from the menu. Refer to EC-83.
2. Turn ignition switch ªONº.
3. Select ªTHRTL POS SENº in ªDATA MONITORº mode with CONSULT-II.
4. Check that output voltage of throttle position sensor is 0.45 to 0.55V. (Throttle valve fully closes.)
SEF175Y
Throttle position sensor voltage: 0.45 to 0.55V
OK or NG
OK©GO TO 14.
NG©GO TO 12.
12 ADJUSTMENT THROTTLE POSITION SENSOR 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. Adjust output voltage to 0.45 to 0.55V by rotating throttle position sensor body.
4. Tighten throttle position sensor bolts.
5. Check the output voltage of throttle position sensor again.
SEF179Y
Throttle position sensor voltage: 0.45 to 0.55V
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 DETECT MULFUNCTIONING PART
Check the throttle position sensor component. Refer to EC-214.
OK or NG
OK©GO TO 10.
NG©Replace throttle position sensor.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-120
Page 845 of 2898
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 9 seconds.
9. Repeat steps 7 and 8 until ªCLSD THL POSº signal changes to ªONº.
SEC576C
©GO TO 19.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONQG
Basic Inspection/Sedan (Cont'd)
EC-121