check engine MITSUBISHI LANCER EVOLUTION IV 1998 Workshop Manual

11-1
ENGINE
CONTENTS
SERVICE SPECIFICATIONS 2. . . . . . . . . . . . . .
SEALANTS 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 2 . . . . . . . . . . . . . . . . . . . . . . . .
ENGINE ADJUSTMENTS 4 . . . . . . . . . . . . . . . . .
1. Drive Belt Tension Check 4 . . . . . . . . . . . . . . .
2. Auto Tensioner Check 5 . . . . . . . . . . . . . . . . . . .
3. Lash Adjuster Check 5 . . . . . . . . . . . . . . . . . . . .
4. Lash Adjuster Replacement 7 . . . . . . . . . . . . . .
5. Ignition Timing Check 7 . . . . . . . . . . . . . . . . . . .
6. Idle Speed Check and Idle Mixture Check 7
7. Compression Pressure Check 7 . . . . . . . . . . . .
8. Manifold Vacuum Check 8 . . . . . . . . . . . . . . . . .
CRANKSHAFT PULLEY 9. . . . . . . . . . . . . . . . . .
CAMSHAFT AND CAMSHAFT
OIL SEAL 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OIL PAN 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CRANKSHAFT OIL SEAL 15 . . . . . . . . . . . . . .
CYLINDER HEAD GASKET 17 . . . . . . . . . . . .
TIMING BE LT . . . . . . . . . . . . . . 21 . . . .
ENGINE ASSEMB LY 32
. . . . . . . . . . . . . . . . . . .

ENGINE – Special Tools / Engine Adjustments11-4
Tool UseName Number
MB991654Cylinder head bolt
wrenchRemoving and reinstalling the cylinder head
bolt
MD998767Tensioner pulley
socket wrenchTiming belt tension adjustment
Recommended
tool MZ203826
by Anzen
Jidosha or
MZ203827 by
BanzaiEngine lifterSupporting the engine assembly during
removal and installation of the transmission
MD991453Engine hanger
assembly
ENGINE ADJUSTMENTS
1. DRIVE BELT TENSION CHECK
NOTE
Use of the auto tensioner eliminates the need for belt tension
adjustment. Check that the indicator mark on the auto
tensioner is in the range of A shown.
If it is outside the specified range (i.e., in range of B shown),
replace the drive belt.
(For the removal and installation of the drive belt, refer to
P.11-9.)
Auto tensioner
Indicator mark
AB

ENGINE – Engine Adjustments11-5
2. AUTO TENSIONER CHECK
(1) Stop the engine from the idle speed and check that the
belt rests within the auto tensioner pulley width.
(2) Remove the drive belt.
(For the removal of the drive belt, refer to P.11-9.)
(3) Fit a spinner handle or similar tool into the tool mounting
hole of the auto tensioner and turn the tensioner clockwise
and counterclockwise to ensure that it does not bind.
(4) If step (1) or (3), or both, have been checked abnormally,
replace the auto tensioner.
(5) Reinstall the drive belt.
3. LASH ADJUSTER CHECK
NOTE
If an unusual knocking noise can be heard immediately after
the engine has started or while it is running and if that is
probably attributable to the lash adjuster, make the following
checks.
(1) Check the engine oil and add or change oil as necessary.
NOTE
(1) If the engine oil level is low, air is taken in through
the oil screen, entering the oil passage.
(2) If the oil level is too high, the cranks agitate oil causing
oil to trap a large amount of air.
(3) Air does not easily separate from a deteriorated oil
that can contain an increased amount of air.
When air trapped in oil for these reasons gets into the
high-pressure chamber of the lash adjuster, the air in
the high-pressure chamber is compressed to shrink the
lash adjuster excessively while the valve is opening,
resulting in an unusual noise occurring. This is the same
symptom developing when the valve clearance is adjusted
to an excessive value.
The problem in this case is gone when air is released
from the lash adjuster.
(2) Start the engine and carry out several cycles (10 or less)
of mild racing*.
If the noise is gone after racing, it indicates that air has
been released from the high-pressure chamber of the
lash adjuster, restoring the lash adjuster to normal
operating conditions.
*: Gradually (extending over a 30-sec. period) increase
the engine speed from idle speed to 3,000 r/min and
then reduce it down to the idle speed gradually
(extending over a 30-sec. period).
NOTE
(1) If the vehicle is parked on a slope for a long time,
the amount of oil in the lash adjuster will decrease,
causing air to get into the high-pressure chamber
when the engine is started.
(2) After the vehicle has been parked for a long time,
oil drains out of the oil passage and it takes a long
time for the oil to reach the lash adjuster. This can
cause air to get into the high-pressure chamber.
Tool mounting hole
Good
MAX
MIN
High-pressure
chamber

ENGINE – Engine Adjustments11-6
(3) If the noise is not eliminated by racing, follow these steps
to check the lash adjuster.
a. Stop the engine.
b. Bring no. 1 cylinder to TDC on the compression stroke.
c. Push the rocker arms indicated by arrow A on the
left to see if they go down.
d. Slowly turn the crankshaft clockwise 360
.
e. Perform the same step as step c for rocker arms
indicated by arrow B.
f. Push the part of the rocker arm which contacts the
top of the lash adjuster. If the rocker arm can be
easily moved down to the bottom, the lash adjuster
is defective, requiring replacement.
When the lash adjuster is replaced, be sure first to
bleed the lash adjuster of air before installation. Then,
perform steps a through e to ensure that no abnormal
symptoms are noted.
NOTE
(1) The leak-down test is an effective means to
accurately determine if the lash adjuster is
operational or not.
(2) For the leak-down test and bleeding procedures,
refer to ENGINE WORKSHOP MANUAL.
If the rocker arm is felt binding and cannot be
pushed downward as you push it, the lash adjuster
is operational. Check for other possible causes
for the noise.
(4) Lash adjuster replacement
Caution
From the cylinder from which the lash adjuster is
to be removed, turn the crankshaft to lower the piston,
as the valve contacts the piston when pushed down.
A rocker arm cannot be removed if it is lifted by the
cam. If this is the case, turn the crankshaft so that
the arm is not lifted.
a. Using the special tool, push the valve downward to
remove the roller rocker arm.
b. Remove the lash adjuster from the cylinder head.
c. Mount a brandnew lash adjuster which has been bled
of air in the cylinder head.
d. Using the special tool, lower the valve and install
the roller rocker arm.
NOTE
To mount the roller rocker arm, first place the pivot
side of the rocker arm on the lash adjuster, then push
down the valve; next, place the slipper side of the
rocker arm on the valve system side.Timing belt side
ABABAA B B
MD998782
MD998782

ENGINE – Engine Adjustments11-7
4. LASH ADJUSTER REPLACEMENT
Refer to (4) of the preceding paragraph.
5. IGNITION TIMING CHECK
Check that ignition timing is at the standard value.
Standard value: approx. 5
BTDC
NOTE
Ignition timing is variable within about ±7
, even under normal
operating.
6. IDLE SPEED CHECK AND IDLE MIXTURE
CHECK
(1) Run the engine at 2,000 to 3,000 r/min for 2 minutes.
(2) Check the CO and HC contents at idle.
Standard value
CO contents: 0.6% or less
HC contents: 300 ppm or less
7. COMPRESSION PRESSURE CHECK
(1) Before inspection, check that the engine oil, starter and
battery are normal. In addition, set the vehicle to the
pre-inspection condition.
(2) Remove all of the spark plugs.
(3) Disconnect the crank angle sensor connector.
NOTE
Doing this will prevent the engine-ECU from carrying out
ignition and fuel injection.
(4) Cover the spark plug hole with a shop towel etc., and
after the engine has been cranked, check that no foreign
material is adhering to the shop towel.
Caution
(1) Keep away from the spark plug hole when
cranking.
(2) If compression is measured with water, oil, fuel,
etc., that has come from cracks inside the cylinder,
these materials will become heated and will gush
out from the spark plug hole, which is dangerous.
Crank angle
sensor connector

ENGINE – Engine Adjustments11-8
(5) Set compression gauge to one of the spark plug holes.
(6) Crank the engine with the throttle valve fully open and
measure the compression pressure.
Standard value
(at engine speed of 250 r/min): 11.5 kg/cm
2
Limit (at engine speed of 250 r/min): 9.7 kg/cm2
(7) Measure the compression pressure for all the cylinders,
and check that the pressure differences of the cylinders
are below the limit.
Limit: Max. 1.0 kg/cm
2
(8) If there is a cylinder with compression or a compression
difference that is outside the limit, pour a small amount
of engine oil through the spark plug hole, and repeat
the operations in steps (5) through (7).
a. If the compression increases after oil is added, the
cause of the malfunction is a worn or damaged piston
ring and/or cylinder inner surface.
b. If the compression does not rise after oil is added,
the cause is a burnt or defective valve seat, or pressure
is leaking from the gasket.
(9) Connect the crank angle sensor connector.
(10)Install the spark plugs.
(11) Install the ignition coil and connect the ignition coil
connector.
(12)Erase the diagnosis codes by keeping the battery minus
(–) cable disconnected for more than 10 seconds.
NOTE
This will erase the diagnosis code resulting from the crank
angle sensor connector being disconnected.
8. MANIFOLD VACUUM CHECK
(1) Before inspection, set the vehicle to the pre-inspection
condition.
(2) Connect a tachometer connector.
(3) Attach a three-way union to the vacuum hose between
the fuel pressure regulator valve and the intake manifold,
and connect a vacuum gauge.
(4) Start the engine and check that idle speed is within
standard value.
Standard value: 850 ± 50 r/min
5. Check the manifold vacuum at idling.
Limit: Min. 55 kPa {410 mmHg}
Compression gauge
Vacuum gauge
Fuel pressure
regulator valve

ENGINE – Cylinder Head Gasket11-20
(3) Tighten the bolts by the following procedure.
StepOperation
1Tighten to 78 Nm {8.0 kgf
m} in the order shown in the
illustration.
2Fully loosen in the reverse order of that shown in the
illustration.
3Tighten to 20 Nm {2.0 kgf
m} in the order shown in the
illustration.
4Mark the head of the cylinder head bolt and cylinder head
by paint, then tighten 90
of a turn in the order shown in
the illustration.
5Tighten 90
of a turn in the order shown in the illustration.
Check that the painted mark of the head bolt is lined up
with that of the cylinder head.
Caution
(1) Always make a tightening angle just 90
. If it is less
than 90
, the head bolt will be loosened.
(2) If it is more than 90
, remove the head bolt and repeat
the procedure from step 1.
COIL RETURN PIPE GASKET INSTALLATION
Install the gasket with the printed portion toward the oil pan.
DHIGH-PRESSURE FUEL HOSE INSTALLATION
(1) Apply a small amount of new engine oil to the O-ring,
then fit the O-ring in the delivery pipe.
Caution
Do not let any engine oil get into the delivery pipe.
(2) Check that the high pressure hose turns smoothly.
If the hose does not turn smoothly, the O-ring is probably
being clamped. Disconnect the high-pressure fuel hose
and check the O-ring for damage. After this, re-install
the hose to the delivery pipe and check that the hose
turns smoothly.
(3) Tighten the mounting bolts to the specification.
Intake sideMB991654
Exhaust sideFront of engine
Step 4
90

Painted markStep 5
90

Painted mark
GasketPrinted portion

ENGINE – Timing Belt11-24
(2) Cracks on rubber back.
(3) Cracks of canvas.
(4) Cracks on rib root.
(5) Cracks on belt sides.
(6) Abnormal wear of belt sides.
NOTE
The sides are normal if they are sharp as if cut by a
knife.
(7) Abnormal wear on teeth.
Initial stage:
Canvas on load side tooth flank worn (Fluffy canvas
fibers, rubber gone and color changed to white, and
unclear canvas texture)
Final stage:
Canvas on load side tooth flank worn down and rubber
exposed (tooth width reduced)
(8) Missing tooth.
AUTO TENSIONER
(1) Check the auto tensioner for possible leaks and replace
as necessary.
(2) Check the rod end for wear or damage and replace as
necessary.
(3) Measure the rod protrusion. If it is out of specification,
replace the auto tensioner.
Standard value: 12 mm
(4) Press the rod with a force of 98 – 196 N {10 – 20 kgf}
and measure its protrusion. If it is out of specification,
replace the auto tensioner.
Standard value: 1 mm or lessCracks
Cracks
on sides Cracks
Cracks on rib root Peeling of
canvas
Tooth missing
12 mm
6EN1033
98 to 196 N {10 to 20 kgf}
Movement

ENGINE – T iming Belt 11-29
(4) Align the timing mark on the oil pump sprocket with its
mating mark.
(5) Remove the plug on the left side of the cylinder block
and insert a Phillips screwdriver (shank diameter 8 mm)
through the hole.
If it can be inserted as deep as 60 mm or more, the
timing marks are correctly aligned. If the inserted depth
is only 20 – 25 mm, turn the oil pump sprocket one turn
and realign timing marks. Then check to ensure that the
screwdriver can be inserted 60 mm or more.
(6) Remove the Phillips screwdriver. Place the oil pump sprocket in a position where its timing mark is one tooth
offset from the mated timing mark in the counterclockwise
direction.
(7) Fit the timing belt over the exhaust side camshaft sprocket, and secure it at the illustrated position using a paper
clip.
(8) Turn the intake side camshaft sprocket as shown to a position where its timing mark is one tooth offset from
the mated timing mark in the counterclockwise direction.
Then, fit the timing belt over the sprocket and secure
it with a paper clip.
NOTE
The intake camshaft will be turned a little clockwise by
the valve spring tension and stabilized in position even
if the belt is clipped at one tooth offset position.
(9) Check to ensure that the timing marks on the intake camshaft sprocket side are in alignment when the exhaust
camshaft sprocket is turned clockwise to align the timing
marks.
NOTE
The timing belt span between the intake and exhaust
sprockets will have 17 cogs.
Screwdriver
Plug
Timing marks
6EN1327
Timing marks

ENGINE – Timing Belt11-30
(10)Fit the timing belt over the idler pulley, oil pump sprocket
and crankshaft sprocket in this order.
NOTE
Be careful that the belt does not become slack.
(11) Fit the timing belt over the tensioner pulley. NOTE
When fitting the timing belt over the tensioner pulley,
turn the intake side camshaft sprocket a little
counterclockwise, as this will facilitate the work.
(12)Turn the crankshaft pulley a little in the illustrated direction to pull up the timing belt at the idler pulley side.
(13)Check to ensure that the timing marks on the crankshaft sprocket, oil pump sprocket and exhaust camshaft
sprocket are all offset one tooth from the corresponding
timing marks in the counterclockwise direction.
(14)Using the special tool, turn the tensioner pulley in the illustrated direction to strain the timing belt. Then, secure
the tensioner temporarily by tightening the retaining bolt
lightly.
NOTE
There must be no slack in the timing belt between the
intake and exhaust camshafts.
(15)Turn the crankshaft to align the timing mark with the mark for No. 1 cylinder top dead center in the compression
stroke.
(16)Set the special tool as shown and screw it in up to the position where the wire inserted in the auto-tensioner
when installing it can be moved lightly.
Crankshaft
sprocket Oil pump
sprocket
Camshaft
sprocket
Crankshaft
sprocket
MD998767
MD998738