VIAS
EC-753
[VQ]
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VIASPFP:14956
DescriptionBBS00565
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
When the engine is running at medium speed, the ECM sends the ON signal to the VIAS control solenoid
valve. This signal introduces the intake manifold vacuum into the power valve actuator and therefore closes
the power valve.
Under this condition, the effective intake manifold length is equivalent to the total length of passage A and pas-
sage B. This long intake manifold provides increased amount of intake air, which results in improved suction
efficiency and higher torque.
When engine is running at low or high speed, the ECM sends the OFF signal to the VIAS control solenoid
valve and the power valve is opened.
Under this condition, the effective intake manifold length is equivalent to the length of passage B. This short-
ened intake manifold length results in enhanced engine output due to reduced suction resistance under high
speeds.
COMPONENT DESCRIPTION
Power Valve
The power valve is installed in intake manifold collector and used to
control the suction passage of the variable induction air control sys-
tem. It is set in the fully closed or fully opened position by the power
valve actuator operated by the vacuum stored in the surge tank. The
vacuum in the surge tank is controlled by the VIAS control solenoid
valve.
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
VIAS control VIAS control solenoid valve Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Battery Battery voltage*
PBIB1822E
PBIB2108E
SERVICE DATA AND SPECIFICATIONS (SDS)
EC-765
[VQ]
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SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Fuel PressureBBS0057G
Idle Speed and Ignition TimingBBS0057H
*: Under the following conditions:
Air conditioner switch: OFF
Electric load: OFF (Lights, heater fan & rear window defogger)
Steering wheel: Kept in straight-ahead position
Mass Air Flow SensorBBS0057I
*: Engine is warmed up to normal operating temperature and running under no load.
Intake Air Temperature SensorBBS0057J
Engine Coolant Temperature SensorBBS0057K
Heated Oxygen Sensor 1 HeaterBBS0057L
Heated Oxygen sensor 2 HeaterBBS0057M
Crankshaft Position Sensor (POS)BBS0057N
Refer to EC-523, "Component Inspection" .
Camshaft Position Sensor (PHASE)BBS0057O
Refer to EC-532, "Component Inspection" .
Throttle Control MotorBBS0057P
Fuel InjectorBBS0057Q
Fuel pressure at idling kPa (bar, kg/cm2 , psi)Approximately 350 (3.5, 3.57, 51)
Target idle speed No load* (in P or N position)VQ23DE: 700 ± 50 rpm
VQ35DE: 625 ± 50 rpm
Air conditioner: ONIn P or N position VQ23DE: 750 rpm or more
VQ35DE: 700 rpm or more
Ignition timing In P or N position 15 ± 5° BTDC
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle0.9 - 1.1V (VQ23DE engine)*
1.0 - 1.3V (VQ35DE engine)*
Temperature °C (°F) Resistance kΩ
25 (77)1.800 - 2.200
80 (176)0.283 - 0.359
Temperature °C (°F)Resistance kΩ
20 (68)2.1 - 2.9
50 (122)0.68 - 1.00
90 (194)0.236 - 0.260
Resistance [at 25°C (77°F)] 3.3 - 4.0Ω
Resistance [at 25°C (77°F)] 5.0 - 7.0Ω
Resistance [at 25°C (77°F)] Approximately 1 - 15Ω
Resistance [at 10 - 60°C (50 - 140°F)]VQ23DE: 13.5 - 17.5Ω
VQ35DE: 11.1 - 14.5Ω
EM-1
ENGINE MECHANICAL
B ENGINE
CONTENTS
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SECTION EM
A
EM
ENGINE MECHANICAL
QR
PRECAUTIONS .......................................................... 5
Precautions Necessary for Steering Wheel Rotation
After Battery Disconnect .......................................... 5
OPERATION PROCEDURE ................................. 5
Precautions for Drain Engine Coolant ...................... 5
Precautions for Disconnecting Fuel Piping .............. 5
Precautions for Removal and Disassembly ............. 5
Precautions for Inspection, Repair and Replace-
ment ......................................................................... 5
Precautions for Assembly and Installation ............... 5
Parts Requiring Angle Tightening ............................. 6
Precautions For Liquid Gasket ................................. 6
REMOVAL OF LIQUID GASKET .......................... 6
LIQUID GASKET APPLICATION PROCEDURE ..... 6
PREPARATION ........................................................... 8
Special Service Tools ............................................... 8
Commercial Service Tools ...................................... 10
NOISE, VIBRATION AND HARSHNESS (NVH)
TROUBLESHOOTING .............................................. 12
NVH Troubleshooting — Engine Noise .................. 12
Use the Chart Below to Help You Find the Cause
of the Symptom. ..................................................... 13
DRIVE BELTS ........................................................... 14
Checking Drive Belts .............................................. 14
Tension Adjustment ................................................ 14
Removal and Installation ........................................ 14
REMOVAL ........................................................... 14
INSTALLATION ................................................... 15
Removal and Installation of Drive Belt Auto-Ten-
sioner ..................................................................... 15
REMOVAL ........................................................... 15
INSTALLATION ................................................... 16
AIR CLEANER AND AIR DUCT ............................... 17
Removal and Installation ........................................ 17
REMOVAL ........................................................... 17
INSPECTION AFTER REMOVAL ....................... 18INSTALLATION ................................................... 18
Changing Air Cleaner Filter .................................... 18
REMOVAL ........................................................... 18
INSTALLATION ................................................... 18
INTAKE MANIFOLD ................................................. 19
Removal and Installation ........................................ 19
REMOVAL ........................................................... 19
INSTALLATION ................................................... 21
INSPECTION AFTER INSTALLATION ................ 22
EXHAUST MANIFOLD AND THREE WAY CATA-
LYST .......................................................................... 23
Removal and Installation ........................................ 23
REMOVAL ........................................................... 23
INSPECTION AFTER REMOVAL ....................... 24
INSTALLATION ................................................... 24
OIL PAN AND OIL STRAINER ................................. 26
Removal and Installation ........................................ 26
REMOVAL ........................................................... 26
INSPECTION AFTER REMOVAL ....................... 28
INSTALLATION ................................................... 28
INSPECTION AFTER INSTALLATION ................ 30
IGNITION COIL ......................................................... 31
Removal and Installation ........................................ 31
REMOVAL ........................................................... 31
INSTALLATION ................................................... 31
SPARK PLUG(PLATINUM-TIPPED TYPE) .............. 32
Removal and Installation ........................................ 32
REMOVAL ........................................................... 32
INSPECTION AFTER REMOVAL ....................... 32
INSTALLATION ................................................... 33
FUEL INJECTOR AND FUEL TUBE ........................ 34
Removal and Installation ........................................ 34
REMOVAL ........................................................... 34
INSTALLATION ................................................... 36
INSPECTION AFTER INSTALLATION ................ 38
ROCKER COVER ..................................................... 39
Removal and Installation ........................................ 39
REMOVAL ........................................................... 39
INSTALLATION ................................................... 40
EM-2 CAMSHAFT ............................................................... 41
Removal and Installation ........................................ 41
REMOVAL ........................................................... 41
INSPECTION AFTER REMOVAL ........................ 44
INSTALLATION .................................................... 47
INSPECTION AFTER INSTALLATION ................ 49
Valve Clearance ...................................................... 50
INSPECTION ....................................................... 50
ADJUSTMENT .................................................... 51
TIMING CHAIN .......................................................... 53
Removal and Installation ........................................ 53
REMOVAL ........................................................... 54
INSPECTION AFTER REMOVAL ........................ 57
INSTALLATION .................................................... 58
OIL SEAL .................................................................. 62
Removal and Installation of Valve Oil Seal ............. 62
REMOVAL ........................................................... 62
INSTALLATION .................................................... 62
Removal and Installation of Front Oil Seal ............. 63
REMOVAL ........................................................... 63
INSTALLATION .................................................... 63
Removal and Installation of Rear Oil Seal .............. 64
REMOVAL ........................................................... 64
INSTALLATION .................................................... 64
CYLINDER HEAD ..................................................... 65
On-Vehicle Service ................................................. 65
CHECKING COMPRESSION PRESSURE ......... 65
Removal and Installation ........................................ 66
REMOVAL ........................................................... 66
INSPECTION AFTER REMOVAL ........................ 67
INSTALLATION .................................................... 68
INSPECTION AFTER INSTALLATION ................ 68
Disassembly and Assembly .................................... 70
DISASSEMBLY ................................................... 70
ASSEMBLY ......................................................... 71
Inspection After Disassembly ................................. 72
VALVE DIMENSIONS .......................................... 72
VALVE GUIDE CLEARANCE .............................. 73
VALVE GUIDE REPLACEMENT ......................... 73
VALVE SEAT CONTACT ..................................... 75
VALVE SEAT REPLACEMENT ........................... 75
VALVE SPRING SQUARENESS ......................... 76
VALVE SPRING DIMENSIONS AND VALVE
SPRING PRESSURE LOAD ............................... 76
ENGINE ASSEMBLY ................................................ 77
Removal and Installation ........................................ 77
REMOVAL ........................................................... 78
INSTALLATION .................................................... 79
INSPECTION AFTER INSTALLATION ................ 80
CYLINDER BLOCK ................................................... 81
Disassembly and Assembly .................................... 81
DISASSEMBLY ................................................... 82
ASSEMBLY ......................................................... 86
How to Select Piston and Bearing .......................... 91
DESCRIPTION .................................................... 91
HOW TO SELECT PISTON ................................. 92
HOW TO SELECT CONNECTING ROD BEAR-ING ....................................................................... 92
HOW TO SELECT MAIN BEARING .................... 95
Inspection After Disassembly .................................. 99
CRANKSHAFT END PLAY .................................. 99
CONNECTING ROD SIDE CLEARANCE ........... 99
PISTON TO PISTON PIN OIL CLEARANCE ....... 99
PISTON RING SIDE CLEARANCE ...................100
PISTON RING END GAP ..................................100
CONNECTING ROD BEND AND TORSION .....101
CONNECTING ROD BIG END DIAMETER ......101
CONNECTING ROD BUSHING OIL CLEAR-
ANCE .................................................................101
CYLINDER BLOCK DISTORTION ....................102
MAIN BEARING HOUSING INNER DIAMETER .103
PISTON TO CYLINDER BORE CLEARANCE ..103
CRANKSHAFT MAIN JOURNAL DIAMETER ...104
CRANKSHAFT PIN JOURNAL DIAMETER ......105
OUT-OF-ROUND AND TAPER OF CRANK-
SHAFT ...............................................................105
CRANKSHAFT RUNOUT ..................................105
CONNECTING ROD BEARING OIL CLEAR-
ANCE .................................................................105
MAIN BEARING OIL CLEARANCE ...................106
MAIN BEARING CRUSH HEIGHT ....................107
CONNECTING ROD BEARING CRUSH
HEIGHT .............................................................107
LOWER CYLINDER BLOCK MOUNTING BOLT
OUTER DIAMETER ...........................................107
CONNECTING ROD BOLT OUTER DIAMETER .107
SERVICE DATA AND SPECIFICATIONS (SDS) ....108
Standard and Limit ................................................108
GENERAL SPECIFICATIONS ...........................108
DRIVE BELT ......................................................108
EXHAUST MANIFOLD ......................................108
SPARK PLUG ....................................................108
CYLINDER HEAD ..............................................108
VALVE ................................................................109
CAMSHAFT AND CAMSHAFT BEARING .........113
CYLINDER BLOCK ............................................113
PISTON, PISTON RING AND PISTON PIN ......114
CONNECTING ROD ..........................................115
CRANKSHAFT ...................................................115
MAIN BEARING .................................................117
CONNECTING ROD BEARING .........................118
VQ
PRECAUTIONS .......................................................119
Precautions Necessary for Steering Wheel Rotation
After Battery Disconnect .......................................119
OPERATION PROCEDURE ..............................119
Precautions for Drain Engine Coolant ...................119
Precautions for Disconnecting Fuel Piping ...........119
Precautions for Removal and Disassembly ..........119
Precautions for Inspection, Repair and Replace-
ment ......................................................................119
Precautions for Assembly and Installation ............119
PRECAUTIONS
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[QR]PRECAUTIONSPFP:00001
Precautions Necessary for Steering Wheel Rotation After Battery DisconnectBBS005KH
NOTE:
This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT
SYSTEM).
Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK″ position.
Always use CONSULT-II to perform self-diagnosis as a part of each function inspection after finishing
work. If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery power is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables.
NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
5. When the repair work is completed, return the ignition switch to the ″LOCK″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of all control units using CONSULT-II.
Precautions for Drain Engine CoolantBBS005KI
Drain engine coolant when engine is cooled.
Precautions for Disconnecting Fuel PipingBBS005KJ
Before starting work, make sure no fire or spark producing items are in the work area.
Release fuel pressure before disassembly.
After disconnecting pipes, plug openings to stop fuel leakage.
Precautions for Removal and DisassemblyBBS005KK
When instructed to use special service tools, use the specified tools. Always be careful to work safely,
avoid forceful or uninstructed operations.
Exercise maximum care to avoid damage to mating or sliding surfaces.
Cover openings of engine system with tape or the equivalent, if necessary, to seal out foreign materials.
Mark and arrange disassembly parts in an organized way for easy troubleshooting and re-assembly.
When loosening nuts and bolts, as a basic rule, start with the one furthest outside, then the one diagonally
opposite, and so on. If the order of loosening is specified, do exactly as specified.
Precautions for Inspection, Repair and ReplacementBBS005KL
Before repairing or replacing, thoroughly inspect parts. Inspect new replacement parts in the same way, and
replace if necessary.
Precautions for Assembly and InstallationBBS005KM
Use torque wrench to tighten bolts or nuts to specification.
EM-6
[QR]
PRECAUTIONS
When tightening nuts and bolts, as a basic rule, equally tighten in several different steps starting with the
ones in center, then ones on inside and outside diagonally in this order. If the order of tightening is speci-
fied, do exactly as specified.
Replace with new gasket, packing, oil seal or O-ring.
Dowel pins are used for several parts alignment. When replacing and reassemling with dowel pins, make
sure that dowel pins are installed in the original portion.
Thoroughly wash, clean, and air-blow each part. Carefully check oil or coolant passages for any restriction
and blockage.
Avoid damaging sliding or mating surfaces. Completely remove foreign materials such as cloth lint or dust.
Before assembly, oil sliding surfaces well.
Release air within route when refilling after draining coolant.
Before starting engine, apply fuel pressure to fuel lines with turning ignition switch “ON” (with engine
stopped). Then make sure that there are no leaks at fuel line connections.
After repairing, start engine and increase engine speed to check engine coolant, fuel, engine oil, and
exhaust gases for leakage.
Parts Requiring Angle TighteningBBS005KN
Use angle wrench [SST: KV10112100] for the final tightening of the following engine parts.
–Cylinder head bolts
–Lower cylinder block bolts
–Connecting rod cap bolts
–Crankshaft pulley bolt (No angle wrench is required as the bolt flange is provided with notches for angle
tightening)
–Balancer unit
Do not use a torque value for final tightening.
The torque value for these parts are for a preliminary step.
Ensure thread and seat surfaces are clean and coated with engine oil.
Precautions For Liquid GasketBBS005KO
REMOVAL OF LIQUID GASKET
After removing the mounting nuts and bolts, separate the mating
surface using seal cutter (SST) and remove the old liquid gasket
sealing.
CAUTION:
Be careful not to damage the mating surfaces.
Tap seal cutter to insert it, and then slide it by tapping on the
side as shown in the figure.
In areas where seal cutter is difficult to use, use plastic hammer
to lightly tap the areas where the liquid gasket is applied.
CAUTION:
If for some unavoidable reason tool such as screwdriver is
used, be careful not to damage the mating surfaces.
LIQUID GASKET APPLICATION PROCEDURE
1. Using scraper, remove the old liquid gasket adhering to the liq-
uid gasket application surface and the mating surface.
Remove the liquid gasket completely from the groove of the
liquid gasket application surface, mounting bolts and bolt
holes.
2. Wipe the liquid gasket application surface and the mating sur-
face with white gasoline (lighting and heating use) to remove
adhering moisture, grease and foreign materials.
PBIC0275E
PBIC0003E
PRECAUTIONS
EM-7
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3. Attach liquid gasket tube to the tube presser (SST).
Use Genuine Liquid Gasket or equivalent.
4. Apply the liquid gasket without breaks to the specified location
with the specified dimensions.
If there is a groove for the liquid gasket application, apply the
liquid gasket to the groove.
As for the bolt holes, normally apply the liquid gasket inside
the holes. Occasionally, it should be applied outside the
holes. Make sure to read the text of service manual.
Within 5 minutes of liquid gasket application, install the mating
component.
If the liquid gasket protrudes, wipe it off immediately.
Do not retighten mounting bolts or nut after the installation.
Wait 30 minutes or more after installation before refilling
engine oil and engine coolant.
CAUTION:
If there are specific instructions in this manual, observe
them.
PBIC2160E
SEM159F
DRIVE BELTS
EM-15
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INSTALLATION
1. With box wrench, and while securely holding the hexagonal part
in center of drive belt auto-tensioner pulley, move the wrench
handle in the direction of arrow (loosening direction of ten-
sioner).
CAUTION:
Avoid placing hand in a location where pinching may
occur if the holding tool accidentally comes off.
Do not loosen the hexagonal part in center of drive belt
auto-tensioner pulley (Do not turn it counterclockwise). If
turned counterclockwise, the complete drive belt auto-
tensioner must be replaced as a unit, including the pul-
ley.
2. Insert a rod approximately 6 mm (0.24 in) in diameter such as short-length screwdriver into the hole of
retaining boss to fix drive belt auto-tensioner pulley.
3. Hook drive belt onto all pulleys except for water pump, and then onto water pump pulley finally.
CAUTION:
Confirm belt is completely set to pulleys.
Check for engine oil, working fluid and engine coolant are not adhered to drive belt and each
pulley groove.
4. Release drive belt auto-tensioner, and apply tension to drive belt.
5. Turn crankshaft pulley clockwise several times to equalize tension between each pulley.
6. Confirm tension of drive belt at indicator (notch on fixed side) is within the possible use range. Refer to
EM-14, "
Checking Drive Belts" .
Removal and Installation of Drive Belt Auto-TensionerBBS0058V
CAUTION:
The complete drive belt auto-tensioner must be replaced as a unit, including the pulley.
REMOVAL
1. Remove splash guard (RH).
2. Remove drive belt. Refer to EM-14, "
Removal and Installation" .
3. Release the fixed drive belt auto-tensioner pulley.
4. Remove drive belt auto-tensioner.
PBIC2627E
1. Drive belt auto-tensioner 2. Water pump pulley
PBIC2170E