EM-29 INFINITI QX4 2001 Factory Service Manual

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 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 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.
SEF572X
15ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 18.
NG©GO TO 11.
11 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-29, 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.
SEF572X
15ɱ5É BTDC (in ªPº or ªNº position)
OK or NG
OK©GO TO 18.
NG©GO TO 13.
BASIC SERVICE PROCEDURE
Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont'd)
EC-48

13 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 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.
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 16.
NG©GO TO 15.
15 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 13.
16 CHECK IGNITION TIMING AGAIN
Check ignition timing again. Refer to Test No. 12.
OK or NG
OK©GO TO 18.
NG©GO TO 17.
17 CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-29, ªInstallationº.
OK or NG
OK©GO TO 15.
NG©1. Repair the timing chain installation.
2. GO TO 13.
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BASIC SERVICE PROCEDURE
Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont'd)
EC-49

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

NVH Troubleshooting Ð Engine NoiseNBEM0005S01Use the chart below to help you find the cause of the symptom.
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
Location of
noiseType of
noiseOperating condition of engine
Source of
noiseCheck itemReference
page Before
warm-upAfter
warm-upWhen
startingWhen
idlingWhen
racingWhile
driving
To p o f
engine
Rocker
cover
Cylinder
headTicking or
clickingC A ÐA BÐTappet
noiseValve clearance EM-54
Rattle C A Ð A B CCamshaft
bearing
noiseCamshaft journal clear-
ance
Camshaft runoutEM-42, 42
Crankshaft
pulley
Cylinder
block
(Side of
engine)
Oil panSlap or
knockÐ A ÐB BÐPiston pin
noisePiston and piston pin
clearance
Connecting rod bush-
ing clearanceEM-63, 70
Slap or
rapA ÐÐBBAPiston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsionEM-64, 64,
65, 66
Knock A B C B B BConnect-
ing rod
bearing
noiseConnecting rod bush-
ing clearance (Small
end)
Connecting rod bearing
clearance (Big end)EM-70, 69
Knock A B Ð A B CMain bear-
ing noiseMain bearing oil clear-
ance
Crankshaft runoutEM-67, 67
Front of
engine
Timing
chain
coverTapping or
tickingA A ÐBBBTiming
chain and
chain ten-
sioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operationEM-29, 20
Front of
engineSqueaking
or fizzingA B ÐBÐCOther
drive belts
(Sticking
or slipping)Drive belts deflectionMA section
(ªChecking
Drive
Beltsº,
ªENGINE
MAINTE-
NANCEº) Creaking A BABABOther
drive belts
(Slipping)Idler pulley bearing
operation
Squall
CreakA B ÐBABWater
pump
noiseWater pump operationLC section
(ªWater
Pump
Inspectionº,
ªENGINE
COOLING
SYSTEMº)
A: Closely related B: Related C: Sometimes related Ð: Not related
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NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting Ð Engine Noise
EM-9

SEM928E
InspectionNBEM0013Check for cracks and excessive wear at roller links. Replace
chain if necessary.
SEM930E
InstallationNBEM00141. Position crankshaft so that No. 1 piston is set at TDC on com-
pression stroke.
SEM929E
2. Install crankshaft sprocket on crankshaft.
IMake sure that mating marks on crankshaft sprocket face
front of engine.
SEM931E
3. Install lower chain guide on dowel pin, with front mark on the
guide facing upside.
SEM430G
4. Press and shrink the secondary chain tensioner sleeve, and fix
it using stopper pins.
ILubricate threads and seat surfaces of camshaft sprocket bolts
with new engine oil.
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TIMING CHAIN
Inspection
EM-29