Page 409 of 1449
ENGINE <4G6> -General Information11A-3
GENERAL INFORMATION
Items4G63
Total displacement mL1,997
Bore×Stroke mm85.0×88.0
Compression ratio8.8
Combustion chamberPentroof type
Camshaft arrangementDOHC
Number of valveIntake8
Exhaust8
Valve timingIntakeOpeningBTDC 21_
ClosingABDC 59_
ExhaustOpeningBBDC 58_
ClosingATDC 18_
Fuel systemElectronically controlled multipoint fuel injection
Rocker armRoller type
Auto-lash adjusterEquipped
Page 410 of 1449

ENGINE -Service Specifications/Sealants11A-4
SERVICE SPECIFICATIONS
ItemsStandard valueLimit
Drive belt tensionVibration frequency Hz (Reference)110 - 144-
Tension N (Reference)245 - 412-
Basic ignition timing5_BTDC±3_-
Ignition timingApproximetely
5_BTDC-
Idle speed r/min850±100-
CO contents %0.1 or less-
HC contents ppm100 or less-
Compression pressure (250 - 400 r/min) kPa1,128951
Compression pressure difference of all cylinder kPa-Max. 98
Intake manifold vacuum kPa-Min. 60
Cylinder head bolt shank length mm-99.4
Timing belt B tension
(Whenchecked)
Vibration frequency Hz52 - 92-
(When checked)Deflection mm (Reference)5-10-
Timing belt B tension
(Whenadjusted)
Vibration frequency Hz76 - 92-
(When adjusted)Deflection mm (Reference)5-7-
Timing belt B tension
(Whenreplaced)
Vibration frequency Hz76 - 92-
(When replaced)Deflection mm (Reference)5-7-
Auto-tensioner rod protrusion amount mm3.8 - 4.5-
Auto-tensioner rod sink in amount mmWithin 1-
SEALANTS
ItemsSpecified SealantsRemarks
Rocker coverMITSUBISHI GENUINE PART MD970389 or
equivalent
Semi-drying
sealant
Rocker cover gasket
equivalentsealant
Cylinder head
Camshaft position sensor support
Oil pan
Camshaft end seal3M ATD Part No. 8660 or equivalent
Page 411 of 1449
ENGINE -Special Tools11A-5
SPECIAL TOOLS
ToolNumberNameUse
MB991502MUT-IIsub
assemblyDMeasuring the drive belt tension
DChecking the ignition timing
DChecking the idle speed
DErasing diagnosis code
DMeasuring the timing belt B tension
MB991668Belt tension meter
setDMeasuring the drive belt tension
(used together with MUT-II)
DMeasuring the timing belt B tension
(used together with MUT-II)
MD998727Oil pan removerFor removing the oil pan
MD998781Flywheel stopperFor fixing the flywheel
MD998776Crankshaft
rear oil seal
installerFor pressfitting the crankshaft rear oil seal
MB990938Installer bar
MD998285Crankshaft
front oil seal
guideFor pressfitting the crankshaft front oil seal
MD998382Crankshaft
front oil seal
installer
MB991654Cylinder head bolt
wrenchFor removal and installation of cylinder head
bolts
Page 412 of 1449
ENGINE -Special Tools11A-6
Tool UseName Number
MB991367Special spannerFor retaining the crankshaft sprocket
MB991385Pin
MB991704Battery harnessMeasuring the timing belt B tension
(used together with MUT-II)
MD998767Tensioner pulley
socket wrenchFor adjusting timing belt tension
MD998738Adjusting boltFor retaining the tensioner arm and the
auto-tensioner
MB991453Engine hanger
attachment
setSupporting the engine assembly during
removal and installation of the transmission
GENERAL
SERVICE
TOOL
MZ203827Engine lifter
Page 413 of 1449

ENGINE -On-vehicle Service11A-7
ON-VEHICLE SERVICE
DRIVE BELT TENSION CHECK
1. Check that the indicator marking of the auto-tensioner
is within the range as shown in the illustration A of the
tensioner bracket.
Caution
Inspection must be carried out after turning the
crankshaft clockwise for more than once.
2. If the marking is outside the range as shown in the
illustration A, replace the drive belt.
NOTE
Due to the adoption of the auto-tensioner, no adjustment
for belt tension is required.
AUTO-TENSIONER CHECK
1. Check that the driver belt stays within the width of the
pulley of the auto-tensioner after turning off the engine
at idle.
2. Remove the drive belt.(Refer to P.11C-15.)
3. Use the 12.7sq. spinner handle and etc. to check that
the auto-tensioner is not stuck by turning it in both
directions.
4. If there is any abnormality in the above - mentioned 1
or 3, replace the auto-tensioner.
5. Install the drive belt.(Refer to P.11C-15.)
To determine whether the auto-tensioner is acceptable can
be done by checking the drive belt tension.
1. Use the following procedure to check the drive belt tension.
(1) Connect the special tool (MB991668) to the MUT-II.
(2) Connect the MUT-IIto the diagnosis connector.
Caution
Connection and disconnection of the MUT-IImust
be carried out after turning the ignition switch
to the “LOCK” (OFF) position.
(3) Turn the ignition switch to the “ON” position and select
“Belt Tension Measurement” from the menu screen.
Indicator
marking
A
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ENGINE -On-vehicle Service11A-8
(4) Hold the special tool (MB991668) to the middle of
the belt between the pulleys (at the place indicated
by the arrow) about 10 - 20 mm away from the rear
surface and so that it is perpendicular to the belt
(within an angle of±15°).
(5) Gently tap the middle of the belt between the pulleys
(at the place indicated by the arrow) with your finger
as shown in the illustration, and check that the
vibration frequency of the belt is within the standard
value.
Standard value: 110 - 144 Hz
Caution
1) Check the vibration frequency of the belt when
the temperature of the surface of the belt is
as close as possible to normal temperature.
2) Do not let any contaminants such as water
or oil get onto the microphone.
3) If strong gusts of wind blow against the
microphone or if there are any loud sources
of noise nearby, the values measured by the
microphone may not correspond to actual
values.
4) If the microphone is touching the belt while
the measurement is being made, the values
measured by the microphone may not
correspond to actual values.
5) Do not take the measurement while the
vehicle’s engine is running.
Use the belt tension gauge and check that the belt tension
of the middle of the belt between pulleys
(at the place indicated by arrow) is within the standard
value.
Standard value: 245 - 412 N
2. If the value is outside the standard value, replace the
drive belt.Power steering
oil pump pulley
Water
pump
pulley
MB991668
10 - 20 mm
15°
15°
With your finger
tap gently
Belt tension
gauge
Power steering
oil pump pulley
Water pump
pulley
Page 415 of 1449

ENGINE -On-vehicle ServiceENGINE -On-vehicle Service11A-9
IGNITION TIMING CHECK
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Turn the ignition switch to “LOCK” (OFF) position and
then connect the MUT-IIto the diagnosis connector.
3. Set up a timing light.
4. Start the engine and run at idle.
5. Check that engine idle speed is within the standard value.
Standard value: 850±100 r/min
6. Select No.17 of the MUT-IIActuator test.
7. Check that basic ignition timing is within the standard
value.
Standard value: 5_BTDC±3_
8. If the basic ignition timing is outside the standard value,
inspect the MPI system while referring to GROUP 13A
- Troubleshooting.
9. Press the MUT-IIclear key (Select a forced driving cancel
mode) to release the Actuator test.
Caution
If the test is not cancelled, a forced driving will
continue for 27 minutes. Driving under this condition
may damage the engine.
10. Check that ignition timing is at the standard value.
Standard value: approximately 5_BTDC
NOTE
(1) Ignition timing is variable within about±7, even under
normal operating.
(2) And it is automatically further advanced by
approximately 5_from standard value at higher
altitudes.
11. Remove the timing light.
12. Turn the ignition switch to “LOCK” (OFF) position and
then remove the MUT-II.
IDLE SPEED CHECK
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Turn the ignition switch to “LOCK” (OFF) position, and
then connect the MUT-IIto the diagnosis connector.
3. Set the timing light.
4. Check that the basic ignition timing is within the standard
value.
MUT-II
MUT-II
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ENGINE -On-vehicle ServiceENGINE -On-vehicle Service11A-10
Standard value: 5_BTDC±3_
5. Run the engine at idle for 2 minutes.
6. Check the idle speed. Select item No. 22 and take a
reading of the idle speed.
Curb idle speed: 850±100 r/min
NOTE
The idle speed is controlled automatically by the idle speed
control (ISC) system.
7. If the idle speed is outside the standard value, check
the MPI components by referring to GROUP 13A -
Troubleshooting.
8. Remove the timing light.
9. Turn the ignition switch to the “LOCK” (OFF) position
and then remove the MUT-II.
IDLE MIXTURE CHECK
1. Before inspection, set the vehicle to the pre-inspection
condition.
2. Turn the ignition switch to the “LOCK” (OFF) position,
and then connect the MUT-IIto the diagnosis connector.
3. Set the timing light.
4. Check that the basic ignition timing is within the standard
value.
Standard value: 5_BTDC±3_
5. Run the engine at 2,500 r/min for 2 minutes.
6. Set the CO, HC tester.
7. Check the CO contents and the HC contents at idle.
Standard value
CO contents: 0.1% or less
HC contents: 100 ppm or less
8. If there is a deviation from the standard value, check the
following items:
DDiagnosis output
DClosed-loop control (When the closed-loop control
is normal, the output signal of the oxygen sensor
changes between 0 - 400 mV and 600 - 1,000 mV
at idle.)
DFuel pressure
DInjector
DIgnition coil, spark plug cable, spark plug
DEvaporative emission control system
DCompression pressure
NOTE
Replace the three way catalyst when the CO and HC
contents are not within the standard value, even though
the result of the inspection is normal on all items.
9. Remove the timing light.
MUT-II