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How to Check Idle Speed and Ignition TimingNJEC0028IDLE SPEEDNJEC0028S05Method A
+Using CONSULT-II
Check idle speed in ªDATA MONITORº mode with CONSULT-
II.
+With GST
Check idle speed in ªMODE 1º with GST.
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Method B (Using Loop wire)
Check the idle speed using loop-wire as shown in the figure.
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JEF438Z
IGNITION TIMINGNJEC0028S06Any of following two methods may be used.
+Method A
a) Attach timing light to loop wire or, combine the three No. 1
ignition coil harnesses and attach the timing light sensor
(attach from above the harness protector) as shown.
b) Check ignition timing.
BASIC SERVICE PROCEDUREQG
How to Check Idle Speed and Ignition Timing
EC-41
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SEF933W
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+Method B
a) Remove No. 1 ignition coil.
b) Connect No. 1 ignition coil and No. 1 spark plug with suitable
high-tension wire as shown, and attach timing light clamp to
this wire.
c) Check ignition timing.
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PreparationNJEC0592+Make sure that the following parts are in good order.
a)Battery
b)Ignition system
c)Engine oil and coolant levels
d)Fuses
e)ECM harness connector
f)Vacuum hoses
g)Air intake system
(Oil filler cap, oil level gauge, etc.)
BASIC SERVICE PROCEDUREQG
How to Check Idle Speed and Ignition Timing (Cont'd)
EC-42
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h)Fuel pressure
i)Engine compression
j)EGR valve operation
k)Throttle valve
l)EVAP system
+On models equipped with air conditioner, checks should
be carried out while the air conditioner is ªOFFº.
+When checking idle speed on models equipped with A/T,
ignition timing and mixture ratio, checks should be carried
out while shift lever is in ªPº or ªNº position.
+When measuring ªCOº percentage, insert probe more
than 40 cm (15.7 in) into tail pipe.
+Turn off headlamps, heater blower, rear window defogger.
+On vehicles equipped with daytime light systems, set
lighting switch to the 1st position to light only small
lamps.
+Keep front wheels pointed straight ahead.
+If engine stops immediately after starting or idle condition
is unstable, perform the following to initialize IACV-AAC
valve:
a)Stop engine and wait 9 seconds.
b)Turn ignition ªONº and wait 1 second.
c)Turn ignition ªOFFº and wait 9 seconds.
+Make sure the cooling fan has stopped.
BASIC SERVICE PROCEDUREQG
Preparation (Cont'd)
EC-43
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OVERALL INSPECTION SEQUENCENJEC0592S01
SEC141C
BASIC SERVICE PROCEDUREQG
Preparation (Cont'd)
EC-44
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Inspection ProcedureNJEC0593
1 INSPECTION START
1. Visually check the following:
+Air cleaner clogging
+Hoses and ducts for leaks
+EGR valve operation
+Electrical connectors
+Gasket
+Throttle valve and throttle position sensor operation
2. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
Ensure engine stays below 1,000 rpm.
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3. Open engine hood and run engine at about 2,000 rpm for about 2 minutes under no-load.
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4. Make sure that no DTC is displayed with CONSULT-II or GST.
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding ªDiagnostic Procedureº.
©GO TO 3.
BASIC SERVICE PROCEDUREQG
Inspection Procedure
EC-45
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3 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.
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 12.
NG©GO TO 4.
4 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-55.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 5.
INCMP©1. Follow the construction of ªIdle Air Volume Leaningº.
2. GO TO 4.
5 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 10.
NG©GO TO 6.
6 REPLACE IACV-AAC VALVE
Replace IACV-AAC valve.
©GO TO 7.
BASIC SERVICE PROCEDUREQG
Inspection Procedure (Cont'd)
EC-46
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7 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-55.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 8.
INCMP©1. Follow the construction of ªIdle Air Volume Learningº.
2. GO TO 4.
8 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 10.
NG©GO TO 9.
9 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-72.
©GO TO 4.
10 CHECK IGNITION TIMING
1. Start engine and warm it up to normal operating temperature.
2. Check ignition timing at idle using a timing light.
SEM872F
M/T: 8ɱ5É BTDC
A/T: 10ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 18.
NG©GO TO 11.
BASIC SERVICE PROCEDUREQG
Inspection Procedure (Cont'd)
EC-47
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11 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-27, ªInstallationº.
OK or NG
OK©GO TO 9.
NG©1. Repair the timing chain installation.
2. GO TO 4.
12 CHECK IGNITION TIMING
1. Start engine and let it idle.
2. Check ignition timing at idle using a timing light.
SEM872F
M/T: 8ɱ5É BTDC
A/T: 10ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 18.
NG©GO TO 13.
13 PERFORM IDLE AIR VOLUME LEARNING
Refer to ªIdle Air Volume Learningº, EC-55.
Which is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©GO TO 14.
INCMP©1. Follow the construction of ªIdle Air volume Learningº.
2. GO TO 13.
14 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 16.
NG©GO TO 15.
BASIC SERVICE PROCEDUREQG
Inspection Procedure (Cont'd)
EC-48