
LUBRICANT
ENGINE COOLING14-3
LUBRICANT
M1141000400338
ItemSpecified coolantQuantity L
Engine coolant (including
condense tank)DIAQUEEN SUPER LONG LIFE COOLANT
or an equivalent4G15.0
4G67.0
SEALANTS
M1141000500324
ItemSpecified sealant
Cylinder block drain plug3M Nut Locking Part No.4171 or equivalent
Water pump <4G1>, Thermostat case
<4G6>, Cooling water outlet hose fitting
<4G6>MITSUBISHI GENUINE Part No.MD970389 or equivalent
SPECIAL TOOLS
M1141000600581
ToolNumberNameUse
B991502
MB991502M.U.T. -II sub
assemblyReading diagno sis co de

ON-VEHICLE SERVICE
ENGINE COOLING14-21
ON-VEHICLE SERVICE
ENGINE COOLANT LEAK CHECKM1141001000300
WARNING
When pressure testing the cooling system,
slowly release cooling system pressure to
avoid getting burned by hot coolant.
CAUTION
•Be sure to completely clean away any mois-
ture from the places checked.
•When the tester is taken out, be careful not to
spill any coolant.
•
ACX01844
Cap adapter
Adapter
AC
Be careful when installing and removing the
tester and when testing not to deform the
filler neck of the radiator.
1. Check that the coolant leve l is up to the filler neck.
Install a radiator tester and apply 160 kPa
pressure, and then check for leakage from the
radiator hose or connections.
2. If there is leakage, repair or replace the
appropriate part.
RADIATOR CAP VALVE OPENING
PRESSURE CHECK
M1141001300389
NOTE: Be sure that the cap is clean before test-
ing. Rust or other foreign material on the cap seal
will cause an improper reading.
AC211643AB
Cap adapter
1. Use a cap adapter to attach the cap to the tester.
2. Increase the pressure until the indicator of the gauge stops moving.
Minimum limit: 83 kPa
Standard value: 93 − 123 kPa
3. Replace the radiator cap if the reading does not remain at or above the limit.
ENGINE COOLANT REPLACEMENT
M1141001200434
WARNING
When removing the radiator cap, use care to
avoid contact with hot coolant or steam.
Place a shop towel over the cap and turn the
cap counterclockwise a little to let the pres
-
sure escape through the vinyl tube. After
relieving the steam pres sure, remove the cap
by slowly turning it counterclockwise.
1. Drain the water from the radiator, heater core and
engine after unplugging the radiator drain plug
and removing the radiator cap.
AC208283AC
Cylinder block
drain plug
<4G1>
Inlet side
AC303355
<4G6>
Inlet side
Cylinder block
drain plug
AB
2. Drain the water in the water jacket by unplugging the drain plug of the cylinder block.
3. Remove the radiator condenser tank and drain
the coolant.
4. Drain the coolant then clean the path of the coolant by injecting water into the radiator from
the radiator cap area.

AC200625
Cylinder block
drain plug
AC
ON-VEHICLE SER VICE
ENGINE COOLING14-22
5.App l y the designa ted sealant to t he scre w area of
th e cylin der block drain plu g , and then tighten to
th e st and ard torq ue.
Sp e c ified s ealant: 3 M Nut Loc king Part
No. 4171 o r e quivale n t
Ti ghtenin g torque:
40 ± 5 N⋅m <4G1>
44 ± 5 N⋅m <4G6>
6.Securely tighten t he drain plug of t he radiator .
7.Reinst all the ra diato r con denser t ank.
CAUTION
Do not use alcohol or methanol anti-freeze or any
engine coolants mixed with alcohol or methanol
anti-freeze. The use of an improper anti-freeze
can cause corrosion of the aluminium compo
-
nents.
AC303612AB
MB991871
AIR HOSE
8. By referring to the section on coolant, select an
appropriate concentration for safe operating
temperature within the range of 30 to 60%. Use
special tool LLC changer (MB991871) to refill the
coolant. A convenient mixture is a 50% water and
50% antifreeze solution (freezing point:
−31°C).
Recommended antifreeze: DIAQUEEN SUPER LONG LIFE COOLANT or equivalent
Quantity:
5.0 L <4G1>
7.0 L <4G6>
NOTE: For how to use special tool MB991871,
refer to its manufacturer’s instructions.
9. Reinstall the radiator cap.
10.Start the engine and let it warm up until the thermostat opens.
11.After repeatedly revving the engine up to 3,000 r/min several times, then stop the engine.
12.Remove the radiator cap after the engine has become cold, and pour in coolant up to the brim.
Reinstall the cap.
CAUTION
Do not overfill the radiator condenser tank.
13.Add coolant to the radiator condenser tank between the "F" and "L" mark if necessary.
CONCENTRATION MEASUREMENT
M1141001100352
Measure the temperature and specific gravity of the
engine coolant to check the antifreeze concentration.
Standard value: 30 − 60% (allowable concentra-
tion range)
Recommended antifreeze: DIAQUEEN SUPER
LONG LIFE COOLANT or equivalent
CAUTION
If the concentration of the anti-freeze is below
30%, the anti-corrosion property will be
adversely affected. In addition, if the concentra
-
tion is above 60%, both the anti-freezing and
engine cooling properties will decrease, affecting
the engine adversely. For these reasons, be sure
to maintain the concentration level within the
specified range.
COOLING FAN MOTOR DRIVE CONTROL
UNIT CHECK
M1141006100250
1. Remove the cooling fan motor drive control unit connector.
AC103195
Y1716AU
1
23
AC
Cooling fan motor
drive control unit
2. Turn the ignition switch to the "ON" position, and
measure the voltage between terminal 1 and 3 at
the harness side connector.
Standard value: system voltage

EXHAUST MANIFOLD
INTAKE AND EXHAUST15-7
INSPECTION
M1151003100616
Check the following points; replace the part if a prob-
lem is found.
Inlet Manifold Check
1. Check for damage or cracking of any part.
2. Clogging of the negative pressure (vacuum) outlet port, or clogging of the exhaust gas recirculation
passages.
3. Using a straight edge and feeler gauge, check for distortion of the cylinder head installation surface.
Standard value: 0.15 mm or less
Limit: 0.20 mm
EXHAUST MANIFOLD
REMOVAL AND INSTALLATION <4G1>
M1151003300568
AC30366250 ± 10 N·m
24 ± 4 N·m
35 ± 6 N·m 17 ± 2 N·m
30 ± 2 N·m
N
3
7 12
4
N
6
8
44 ± 5 N·m
AB
9
5N
30 ± 2 N·m
30 ± 2 N·m
30 ± 2 N·m
(Engine oil)
8.Battery wirin g ha rne s s clamp
9.Inlet manifold st ay
10.Inlet manifold
11.Inlet manifold gask et
12.Emission vacuu m hose & pipe and
emis
sion s o lenoid valve assembly
13.EGR v a lve
14.EGR v a lve gasket
Remo va l st ep s ( C o n t in u e d)

STARTING SYSTEM
ENGINE ELECTRICAL16-22
REMOVAL AND INSTALLATION <4G6>
M1162001001278
Pre-removal and Post-installation Operation
•Air Cleaner Assembly Removal and Installation (Refer to
GROUP 15 P.15-3).
•Under Cover Removal and Installation
AC304005
521
6
49 ± 9 N·m 18 ± 3 N·m
9.0 ± 2.0 N·m
30 ± 3 N·m
AB
4 3
12 ± 2 N·m
Removal steps
1.Starter cover
2.Starter connector and terminal
3.Clutch release cylinder connecting
bolts
4.Clutch hose clamp
<>5.Sta rte r as se mb ly
6.Starter cover bracket
REMOVA L SER VICE POINT
<> STARTER ASSEMBL Y REMOV A L
Remove the st arter assembly from above the veh i-
cle.

IGNITION SYSTEM
ENGINE ELECTRICAL16-30
IGNITION SYSTEM
GENERAL INFORMATIONM1163000100294
This system is equipped with two ignition coils (A and
B) with built-in power transistors for the No. 1 and
No. 4 cylinders and the No. 2 and No. 3 cylinders
respectively.
Interruption of the primary current flowing in the pri-
mary side of ignition coil A generates a high voltage
in the secondary side of ignition coil A. The high volt
-
age thus generated is applied to the spark plugs of
No. 1 and No. 4 cylinders to generate sparks. At the
time that the sparks are generated at both spark
plugs, if one cylinder is at the compression stroke,
the other cylinder is at the exhaust stroke, so that
ignition of the compressed air/fuel mixture occurs
only for the cylinder which is at the compression
stroke.
In the same way, when the primary current flowing in
ignition coil B is interrupted, the high voltage thus
generated is applied to the spark plugs of No. 2 and
No. 3 cylinders.
The engine-ECU
turns the two power transistors inside the ignition
coils alternately on and off. This causes the primary
currents in the ignition coils to be alternately inter
-
rupted and allowed to flow to fire the cylinders in the
order 1-3-4-2.
The engine-ECU
determines which ignition coil should be controlled
by means of the signals from the camshaft position
sensor which is incorporated in the camshaft and
from the crank angle sensor which is incorporated in
the crankshaft. It also detects the crankshaft position
in order to provide ignition at the most appropriate
timing in response to the engine operation condi
-
tions. It also detects the crankshaft position in order
to provide ignition at the most appropriate timing in
response to the engine operation conditions.
When the engine is cold or operated at high alti-
tudes, the ignition timing is slightly advanced to pro-
vide optimum performance.
When the automatic transmission shifts gears, the
ignition timing is also retarded in order to reduce out
-
put torque, thereby alleviating shifting shocks.
SYSTEM DIAGRAM
AK101074
Air flow sensor
<4G6> MAP sensor <4G1>
Intake air temperatur
sensor
Engine coolant
temperature sensor
Camshaft position
sensor
Crank angle sensor
Barometric pressure
sonsor <4G6>
Detonatoin sensor
Ignition switch-ST Engine-A/T-
ECU Engine-ECU
Ignition coil B
Cylinder No. 23 4
AG
1
Spark plug Ignition coil A
Ignition
switch
Battery

IGNITION SYSTEM
ENGINE ELECTRICAL16-33
SPARK PLUG CHECK AND CLEANING
<4G6>
M1163004300353
CAUTION
When pulling off the spark plug cable from the
plug always hold the cable cap, not the cable.
1. Remove the spark plug cables.
2. Remove the spark plugs.
CAUTION
•Do not attempt to adjust the gap of the iridium
plug.
•
AKX00383 AL
Platinum
tipIridium
tip
Always use a plug cleaner and finish cleaning
within 20 seconds. Do not use wire brushes.
Otherwise, the iridium and platinum tip may
be damaged.
3. Check the plug gap and re
place if the limit is
exceeded.
Standard value: 1.0 − 1.1 mm
Limit: 1.3 mm
CAUTION
Be careful not to allow foreign matter in cylin-
ders.
4. Clean the engine plug holes.
5. Install the spark plugs.
CAMSHAFT POSITION SENSOR CHECK
M1163004400219
Check the camshaft position sensor circuit if
self-diagnosis code No. P0340 is shown.
(Refer to GROUP 13A − Troubleshooting − Inspection
chart for diagnosis code <4G1>
P.13A-15 or GROUP
13B − Troubleshooting − Inspection chart for diagnosis
code <4G6>
P.13B-15 ).
CRANK ANGLE SENSOR CHECK
M1163004500272
Check the crank angle sensor circuit if self-diagnosis
code No. P0335 is shown.
(Refer to GROUP 13A − Troubleshooting − Inspection
chart for diagnosis code <4G1>
P.13A-15 or GROUP
13B − Troubleshooting − Inspection chart for diagnosis
code <4G6>
P.13B-15 ).
DETONATION SENSOR CHECKM1163002900047
Check the detonation sensor circuit if self-diagnosis
code No. P0325 is shown.
(Refer to GROUP 13A − Troubleshooting − Inspection
chart for diagnosis code <4G1>
P.13A-15 or GROUP
13B − Troubleshooting − Inspection chart for diagnosis
code <4G6>
P.13B-15).
IGNITION SECONDARY VOLTAGE
WAVEFORM CHECK USING AN
OSCILLOSCOPE
M1163001700170
MEASUREMENT METHOD
1. Clamp the secondary pickup around the spark
plug cable.
NOTE: .
•The peak ignition voltage will be reversed
when the spark plug cables No. 2 and No. 4,
or No. 1 and No. 3 cylinders are clamped.
•Because of the two-cylinder simultaneous igni-
tion system, the waveforms for two cylinders in
each group appear during waveform observa
-
tion (No. 1 cylinder - No. 4 cylinder, No. 2 cyl-
inder - No. 3 cylinder). However, waveform
observation is only applicable for the cylinder
with the spark plug cable clamped by the sec
-
ondary pickup.
•Identifying which cylinder waveform is dis-
played can be difficult. For reference, remem-
ber that the waveform of the cylinder attached
to the secondary pickup will be displayed as
stable.
2. Clamp the spark plug cable with the trigger pickup.
NOTE: Clamp the trigger pickup to the same
spark plug cable clamped by the secondary
pickup.

IGNITION SYSTEM
ENGINE ELECTRICAL16-35
Observation Conditions (The only change from above condition is the pattern selector.)
Pattern selectorDisplay
AKX01275
kV
Secondary ignition
voltage wave pattern 0
2NO. 1 cylinder
NO. 3 cylinder
ignition noise
Newtral section NO. 4 cylinder
NO. 2 cylinder
ignition noise
Time
AC
WA VEFORM OBSER V A T ION POINTS
Point A: The he ight, len g th and s l ope of th e sp a r k line sho w the following trends (Re f er to abnorma l
wave
form exam ples, 1 , 2, 3 a nd 4).
Spark linePlug gapCondition of
electrodeCompression
force Concentration
of air mixtureIgnition
timingSpark plug
cable
LengthLongSmallNormalLowRichAdvancedLeak
ShortLargeLarge wearHigh LeanRetardedHigh
resistance
HeightHighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLow RichAdvancedLeak
SlopeLargePlug is fouled−−−−
Point B: Number of v i bra t ion in red uction vi bra t ion sec tion (Refer to a bnormal wavefo r m examp l e 5)
Number of vibrationsCoil and condenser
3 or moreNormal
Except aboveAbnormal
Point C: Number of v i bra t ions a t beginnin g of dwell se ction (Refer to a bnormal wave form exam ple 5)
Number of vibrationsCoil
5 − 6 or higherNormal
Except aboveAbnormal
Point D: Ignition volt a g e height (distribution per each cylinder) s hows the follo wing tren ds.
Ignition
voltagePlug gapCondition of
electrodeCompression
forceConcentration
of air mixtureIgnition
timingSpark plug
cable
HighLargeLarge wearHighLeanRetardedHigh
resistance
LowSmallNormalLowRichAdvancedLeak