1998 MITSUBISHI LANCER EVOLUTION IV check engine

MANUAL TRANSMISSION – Transmission Assembly22A-7
TRANSMISSION ASSEMBLY
REMOVAL AND INSTALLATION
Pre-removal Operation
(1) Transmission Oil Draining (Refer to P.22A-3.)
(2) Transfer Oil Draining (Refer to P.22A-3.)
(3) Under Cover Removal
(4) Front Exhaust Pipe Removal (Refer to GROUP 15.)
(5) Battery and Battery Tray Removal
(6) Air Cleaner Assembly RemovalPost-installation Operation
(1) Air Cleaner Assembly Installation
(2) Battery and Battery Tray Installation
(3) Front Exhaust Pipe Installation
(Refer to GROUP 15.)
(4) Under Cover Installation
(5) Transfer Oil Supplying (Refer to P.22A-3.)
(6) Transmission Oil Supplying (Refer to P.22A-3.)
(7) Shift Lever Operation Check
(8) Speedometer Operation Check
1
2
34 5
6
7
8 8
Unit: Nm {kgfm}
49 {5.0} 98 {10.0}*
88 {9.0}19 {1.9}
48 {4.9}19 {1.9}
Removal steps
1. Shift cable and select cable con-
nection
2. Backup lamp switch connector
3. Vehicle speed sensor connector
A4. Starter motor
5. Clutch release cylinder connection
6. Transmission assembly upper part
coupling bolts7. Transmission mount bracket
8. Transmission mount stopper

Engine assembly supporting
Caution
Mounting locations marked by * should be
provisionally tightened, and then fully tightened
when the body is supporting the full weight of the
engine.

MANUAL TRANSMISSION OVERHAUL – Sealants and Adhesives22B-5
SEALANTS AND ADHESIVES
TRANSMISSION
ItemsSpecified sealants and adhesives
Clutch housing-transmission case mating surfaceTHREEBOND 1216
Control housing-transmission case mating surface
Under cover-transmission case mating surface
Air breatherTHREEBOND 1501
Center differential drive gear boltTHREEBOND 1303 or LOKTITE 648
TRANSFER
ItemsSpecified sealants and adhesives
Air breatherTHREEBOND 1501
FORM-IN-PLACE GASKET
The transmission has several areas where the form-in-place gasket (FIPG) is in use. To ensure that
the gasket fully serves its purpose, it is necessary to observe some precautions when applying the gasket.
Bead size, continuity and location are of paramount importance. Too thin a bead could cause leaks.
Too thick a bead, on the other hand, could be squeezed out of location, causing blocking or narrowing
of the fluid feed line. To eliminate the possibility of leaks from a joint, therefore, it is absolutely necessary
to apply the gasket evenly without a break, while observing the correct bead size.
DISASSEMBLY
The parts assembled with the FIPG can be easily disassembled without use of a special method. In
some cases, however, the sealant between the joined surfaces may have to be broken by lightly striking
with a mallet or similar tool. A flat and thin gasket scraper may be lightly hammered in between the
joined surfaces. In this case, however, care must be taken to prevent damage to the joined surfaces.
SURFACE PREPARATION
Thoroughly remove all substances deposited on the gasket application surfaces, using a gasket scraper
or wire brush. Check to ensure that the surfaces to which the FIPG is to be applied is flat. Make sure
that there are no oils, greases and foreign substances deposited on the application surfaces. Do not
forget to remove the old sealant remaining in the bolt holes.
FORM-IN-PLACE GASKET APPLICATION
Applied FIPG bead should be of the specified size and without breaks. Also be sure to encircle the
bolt hole circumference with a completely continuous bead. The FIPG can be wiped away unless it is
hardened. While the FIPG is still moist (in less than 10 minutes), mount the parts in position. When
the parts are mounted, make sure that the gasket is applied to the required area only. In addition, do
not apply any oil or water to the sealing locations or start the engine until a sufficient amount of time
(about one hour) has passed after installation is completed.
The FIPG application procedure may vary on different areas. Observe the procedure described in the
text when applying the FIPG.

REAR AXLE – Special Tools / Troubleshooting 27-5
MB990988NumberNameO.D. mm
1MB990551Box–
2MB990989Base–
3(MB990990)Tool A25
(MB990991)Tool B28
(MB990992)Tool C31
MB990925
Brass bar
Bar (one-touch type)Toolbox
Installer adapter
Tool number (MB990925)O.D. mmTool number (MB990925)O.D. mm
AMB99092639.0AMB99093363.5
MB99092745.0MB99093467.5
MB99092849.5MB99093571.5
MB99092951.0MB99093675.5
MB99093054.0MB99093779.0
MB99093157.0BMB990938–
MB99093261.0CMB990939–
TROUBLESHOOTING
1. BASIC TROUBLESHOOTING CONDITIONS
Before starting the troubleshooting procedure, make sure that the following items have been checked
okay.

The correct steering wheel has been properly installed in the neutral position of the steering column
shaft.

Tire and wheel sizes are correct with correct specifications. Inflation pressure, balance, and wear
conditions are okay.

Wheel alignment is correct.

The engine, suspension, and other parts have not been remodeled so as to affect the AYC system.
2. DIAGNOSIS FUNCTION
READING THE DIAGNOSIS CODE
Read the diagnosis code using AYC warning lamp.

REAR AXLE – Troubleshooting 27-21
5. INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection
procedure No.Ref. page
AYC warning lamp does not light up when the ignition key is turned to “ON” (engine
stationary).127-21
AYC warning lamp remains lit up after the engine has started.227-22
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.327-22
Rear tires are noisy during low-speed cornering.
Vehicle skews.427-23
6. INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
AYC warning lamp does not light up when the ignition key
is turned to “ON” (engine stationary).
Probable cause
The lamp power supply circuit is probably open-circuited, lamp bulb is out, or the
circuit between AYC warning lamp and AYC-ECU or AYC-ECU itself is defective.
Blown fuse

AYC warning lamp out

Defective harness or connector

Defective AYC-ECU
NG
Check and repair the harness between
ignition switch (IG
2) and AYC warning
lamp.
OK
Check the trouble symptom.
OK
Replace combination meter.
NG
Check the harness between AYC
warning lamp and AYC-ECU.NG
Repair
OK
Check the trouble symptom.OK
Replace AYC-ECU.
OK
Check the following connectors:
B-96, B-94, B-08NG
Repair
OK
Measure at B-96 AYC-ECU connector.

Disconnect the connector and
measure at the harness side.

Ignition switch: ON

Warning lamp when 36 is grounded
to body
OK:Lit upNGCheck the lamp bulb.NG
Replace
Measure at B-08 combination meter
connector.

Disconnect the connector and
measure at the harness side.

Ignition switch: ON

Voltage across 48 and body ground
OK:Battery voltageNGCheck the following connectors:
B-08, B-74, B-76NG
Repair

REAR AXLE – Troubleshooting 27-22
INSPECTION PROCEDURE 2
AYC warning lamp remains lit up after the engine has
started.
Probable cause
The AYC warning lamp ON circuit is probably short-circuited.
Defective combination meter

Defective harness (short-circuit)

Defective AYC-ECU
NOTE
This symptom is limited only when AYC-ECU power supply is in normal condition and the diagnosis
code is correct.
OK
Replace combination meter.
NO
Check the harness between AYC
warning lamp and AYC-ECU.NG
Repair
Does the AYC warning lamp goes out
when the B-96 AYC-ECU connector
is disconnected?YESReplace AYC-ECU.
INSPECTION PROCEDURE 3
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.
Probable cause
The hydraulic oil level is probably low, there is an oil leak, the hydraulic unit is defective,
or the torque transfer differential is defective.
Low hydraulic oil level

Oil leak

Defective hydraulic unit

Defective torque transfer differential
NOTE
This symptom is limited only when the diagnosis code is correct.
NG
Replace the hydraulic unit.
NG
Replace the torque transfer differential.
Check the trouble symptom.
NG
Replace AYC fluid.
OK
Correct
Check the trouble symptom.NO
Replace the torque transfer differential.
OK
Is foreign matter trapped in the hydrau-
lic line?YES
Repair
OK
Check the AYC for operation.OKCheck the AYC fluid.
NG
Add hydraulic oil.
NG
Check hydraulic pressure.NGBleed the system of air.
Check the hydraulic oil level.NGCheck for oil leak.OK
Repair

REAR AXLE – Troubleshooting 27-24
7. CHECK AT AYC-ECU TERMINALS
7-1 TERMINAL VOLTAGE LISTING
(1) The voltage is to be measured across each terminal and ground terminal.
(2) Fig. below shows the arrangement of the terminals.
Terminal
No.Check itemCheck requirementNormally
1Lateral acceleration sensorIgnition switch: ON2.4 – 2.6 V
(horizontal position)
2Longitudinal acceleration
sensor ground
Lateral acceleration sensor
groundAt all times0 V
3Longitudinal acceleration
sensorIgnition switch: ON2.4 – 2.6 V
(horizontal position)
4Steer sensor (ST-2)Engine: Idle speed
Turn steering wheel slowly.0 V ↔ approx. 3 V
flashing
5Steer sensor (ST-1)Engine: Idle speed
Turn steering wheel slowly.0 V ↔ approx. 3 V
flashing
6*1FR wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
7*1FL wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
8*1RR wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
9*1FL wheel speedVehicle stationary1 V or less
Forward vehicle slowly.0 – 5 V
10Diagnosis selection inputBattery voltage
11Stop lamp switchIgnition switch:
ON
Stop lamp switch: ONBattery voltage
ON
Stop lamp switch: OFF1 V or less
12*1ABS monitorWhen ABS monitor is activatedBattery voltage
When ABS monitor is deactivated1 V or less
17Steer sensor (ST-N)Engine:
Idle speed
Steering wheel: Neutral position0.5 V or less
Idle speed
Steering wheel: Turned 90 from
neutral position2.5 – 3.5 V

REAR AXLE – On-vehicle Service 27-31
7. SPEED SENSOR OUTPUT VOLTAGE
MEASUREMENT ABS>
(1) Lift up the vehicle and release the parking brake.
(2) Disconnect the AYC-ECU harness connector and take
measurements on the harness side connector.
Caution
Insert the probe from the harness side with the double
lock of the connector unlocked. Inserting it to the
terminal side could result in poor contact.
(3) Turn the wheel to be tested at about 1/2 to one
revolution/sec. and check for the output voltage using
a circuit tester (AC mV range) or oscilloscope.
Terminal nos.
Front LHFront RHRear LHRear RH
7698
20192221
Output voltage:
When circuit tester is used: 70 mV or more
When oscilloscope is used: 200 mVp-p or more
(4) If the output voltage is lower than the above value, it
is probably attributable to the following faults. Check or
replace the speed sensor as necessary.
Excessive clearance between the pole piece and rotor
of the speed sensor
Defective speed sensor
Waveform Check Using Oscilloscope
Check the harness and connector of the speed sensor for
connection. Then, use an oscilloscope to check for output
voltage waveform of each speed sensor as follows.
Start the engine and monitor the sensor by turning the wheel;
for a driving wheel, let it turn by shifting into the 1st gear
and for a driven wheel turn it manually at a constant speed.
NOTE
(1) Waveform may be observed by actually running the
vehicle.
(2) The output voltage is low when the wheel speed remains
low and builds up as the wheel speed increases.
AYC-ECU connector harness side
When turned manually
At idle (5 to 6 km/h)
1st gear

REAR AXLE – On-vehicle Service 27-32
Waveform Observation Points
SymptomProbable causeAction
Waveform amplitude is too small, or no
waveform.Defective speed sensorReplace sensor.
Waveform amplitude varies greatly. (No
problem ifthe smallest amplitude is 100
Excessive axle hub lateral and radial runoutReplace hub.
problem if the smallest amplitude is 100
mV or more)Poor AYC-ECU groundingRepair.
Noise on waveform or disturbed
waveform
Open-circuited sensorReplace sensor.
waveform
Open-circuited harnessRepair harness.
Improperly mounted speed sensorCorrect sensor installation.
Missing or collapsed rotor toothReplace rotor.
Caution
Since the speed sensor cable follows the movement of the front or rear suspension, it may be
open-circuited only when the vehicle is run on rough roads and not on ordinary road. The speed
sensor output voltage waveform should therefore be checked also by rocking the sensor harness
so that driving on rough roads may be simulated.
8. ACTION WHEN BATTERY RUNS OUT
When the engine is started using a booster cable where the
battery has completely run down and you attempt to start
the vehicle without waiting for the battery to recover a certain
charge, the engine can misfire and you just cannot start to
move it. In such cases, charge the battery sufficiently; or,
remove the AYC fusible link from the engine compartment
relay box to make AYC inactive before attempting to start
the vehicle. When the fusible link is removed, the AYC warning
lamp lights up. After the battery has been recharged, fit the
fusible link back again and start the engine to ensure that
the AYC warning lamp is off.AYC fusible link