air condition MITSUBISHI LANCER EVOLUTION IV 1998 User Guide

MPI – Troubleshooting13-16
Code No. 64 Alternator FR Terminal SystemProbable cause
Range of Check
Engine speed is approximately 50 r/min or more.
Set conditions
Input voltage at the alternator FR terminal is 4.5 V or more for 20 seconds.Open circuit in alternator FR terminal circuit
Malfunction of the engine-ECU.
OK
Replace the alternator.
NG
Check the harness wire between
the engine-ECU and alternator
connector.NG
Repair
OK
Check trouble symptom.
Measure at the alternator connec-
tor
Connect the connector.
(Use test harness MB991519.)
Voltage between 4 (blue clip)
and earth
(Engine: Idling)
(Radiator fan: Stopped)
(Headlamp: OFF → ON)
(Brake lamp: OFF → ON)
(Rear defogger switch: OFF
→ ON)
OK:Voltage drops by 0.2 to
3.5 V.NGMeasure at the alternator connec-
tor A-05.
Disconnect the connector, and
measure at the harness side.
Voltage between 4 and earth
(Ignition switch: ON)
OK:4.8 – 5.2 VNGCheck the following connec-
tors:
B-60, A-88NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between
the engine-ECU and alternator
connector.NG
Repair
OK
Replace the engine-ECU.
OK
Check the following connector:
A-05NG
Repair
OK
Replace the engine-ECU.

MPI – Troubleshooting13-18
5. SERVICE DATA LIST

Item
No.Inspection
itemInspection contentsNormal condition
11Oxygen
sensorEngine: After having been warmed
up
Air/fuel mixture is made leaner when
When at 4,000 r/min, engine is
suddenly decelerated200 mV or less
Air/fuel mixture is made leaner when
decelerating, and is made richer
when racing.
When engine is suddenly
raced600 – 1,000 mV
Engine: After having been warmed
up
The ox
ygen sensor signal is used to
Engine is idling400 mV or less
(Chan
ges)The oxygen sensor signal is used to
check the air/fuel mixture ratio, and
control condition is also checked by
the ECU.2,500 r/min
(Changes)
600 – 1,000 mV
12Air flow
sensor*
Engine coolant temperature:
8095C
Engine is idling17 – 43 Hz
sensor*80 – 95C
Lamps, electric cooling fan and
all accessories: OFF
2,500 r/min46 – 86 Hz
all accessories: OFF
Transmission: NeutralEngine is racedFrequency increases
in response to racing
13Intake air
temperature
sensor
Ignition switch: ON or with engine
runningWhen intake air temperature
is –20C–20C
sensorWhen intake air temperature
is 0C0C
When intake air temperature
is 20C20C
When intake air temperature
is 40C40C
When intake air temperature
is 80C80C
14Throttle
position
Ignition switch: ONSet to idle position300 – 1,000 mV
position
sensor
Gradually openIncreases in proportion
to throttle opening
angle
Open fully4,500 – 5,500 mV
16Power
supply
voltageIgnition switch: ONSystem voltage
18Cranking
signal Ignition switch: ONEngine: StoppedOFF
g
(ignition
switch-ST)Engine: CrankingON
NOTE
*: When the car is new (distance it travelled is less than 500 km), output frequency of the air flow sensor may
become about 10% higher.

MPI – Troubleshooting13-21

Descriptions other than those given below are the same as for the EVOLUTION-IV.
Item
No.Inspection
itemInspection contentsNormal condition
12Air flow
sensor*1Engine coolant temperature:
80–95C
Engine is idling12 – 38 Hz
sensor*180 – 95C
Lamps, electric cooling fan and
all accessories: OFF
2,500 r/min36 – 76 Hz
all accessories: OFF
Transmission: NeutralEngine is racedFrequency increases
in response to racing
41Injector
drive time*2Engine: Cranking*2When engine coolant temper-
ature is 0C27 – 40 ms
When engine coolant temper-
ature is 20C14.5 – 21.7 ms
When engine coolant temper-
ature is 80C3.8 – 5.6 ms
Injector
drive time*3Engine coolant temperature:
8095C
Engine is idling0.9 – 2.1 ms
drive time *380 – 95C
Lamps, electric cooling fan and
all accessories: OFF
2,500 r/min0.7 – 1.9 ms
all accessories: OFF
Transmission: NeutralWhen engine is suddenly
racedIncreases
44Ignition
advance
Engine: After having been
warmed up
Engine is idling0 – 13BTDC
advancewarmed up
Timing lamp is set.2,500 r/min24 – 44BTDC
NOTE
*1: In a new vehicle (driven approximately 500 km or less), the air flow sensor output frequency is sometimes
10 % higher than the standard frequency.
*2: The injector drive time represents the time when the cranking speed is at 250 r/min or below when the power
supply voltage is 11 V.
*3: In a new vehicle (driven approximately 500 km or less), the injector drive time is sometimes 10 % longer than
the standard time.

MPI – Troubleshooting13-22
6. ENGINE-ECU INSPECTION
6-1 TERMINAL VOLTAGES
Engine ECU connector
Terminal
No.Check itemCheck condition (Engine condition)Normal condition
1No.1 injectorWhile engine is idling after having been warmed up,
suddenly depress the accelerator pedal
Momentarily drops
slightlyfrom 1114V
14No.2 injector
suddenly depress the accelerator pedal.slightly from 11 – 14 V.
2No.3 injector
15No.4 injector
3Fuel pressure control
valve
Ignition switch: ONBattery voltage
valve
Engine: Cranking to idling (within about two minutes)0 – 3 V to battery
voltage
4Stepper motor coil (A1)Engine: Immediately after engine has been started
f
or warming up
Changes repeatedly
f
rom battery voltage to
17Stepper motor coil (A2)
for warming upfrom battery voltage to
0 – 6 V and from 0 – 6
V to battery voltage5Stepper motor coil (B1)V to battery voltage.
18Stepper motor coil (B2)
6Secondary air control
solenoid valveIgnition switch: ONBattery voltage
8Fuel pump relayIgnition switch: ONBattery voltage
Engine: Idling0 – 3 V
10Power transistor unit
(A)Engine speed: 3,000 r/min0.3 – 3.0 V
23Power transistor unit
(B)
11Wastegate solenoid
valve
Ignition switch: ONBattery voltage
valve
Engine: At idle after having been warmed up (when
premium gasoline is used)0 – 3 V
12Power supplyIgnition switch: ONBattery voltage
25
19Air flow sensor reset
signal
Engine: Idling0 – 1 V
signal
Engine speed: 3,000 r/min6 – 9 V
20Fan motor relay (HI)Fan not operating (coolant temperature: 90C or
below)Battery voltage
Fan at high speed (coolant temperature: 105C or
above)0 – 3 V

MPI – Troubleshooting13-24
Terminal
No.Normal condition Check condition (Engine condition) Check item
72Intake air temperature
sensorIgnition switch: ONWhen intake air tempera-
ture is 0C3.2 – 3.8 V
When intake air tempera-
ture is 20C2.3 – 2.9 V
When intake air tempera-
ture is 40C1.5 – 2.1 V
When intake air tempera-
ture is 80C0.4 – 1.0 V
76Oxygen sensorEngine: Running at 2,000 r/min after having been
warmed up (Check using a digital type voltmeter)0 ↔ 0.8 V
(Changes repeatedly)
80Backup power supplyIgnition switch: OFFBattery voltage
81Sensor impressed
voltageIgnition switch: ON4.5 – 5.5 V
82Ignition switch-IGIgnition switch: ONBattery voltage
83Engine coolant
temperature sensorIgnition switch: ONWhen engine coolant
temperature is 0C3.2 – 3.8 V
When engine coolant
temperature is 20C2.3 – 2.9 V
When engine coolant
temperature is 40C1.3 – 1.9 V
When engine coolant
temperature is 80C0.3 – 0.9 V
84Throttle position sensorIgnition switch: ONSet throttle valve to idle
position0.3 – 1.0 V
Fully open throttle valve4.5 – 5.5 V
85Barometric pressure
sensor
Ignition switch: ONWhen altitude is 0 m3.7 – 4.3 V
sensor
When altitude is 1,200 m3.2 – 3.8 V
86Vehicle speed sensorIgnition switch: ON
Move the vehicle slowly forward0 ↔ 5 V
(Changes repeatedly)
87Idle position switchIgnition switch: ONSet throttle valve to idle
position0 – 1 V
Slightly open throttle
valve4 V or more
88Camshaft position
sensor
Engine: Cranking0.4 – 3.0 V
sensor
Engine: Idle speed0.5 – 2.0 V
89Crank angle sensorEngine: Cranking0.4 – 4.0 V
Engine: Idle speed1.5 – 2.5 V
90Air flow sensorEngine: Idle speed2.2 – 3.2 V
Engine speed: 2,500 r/min

MPI – Troubleshooting13-25
6-2 RESISTANCE AND CONTINUITY BETWEEN HARNESS SIDE CONNECTORS AND
TERMINALS
Engine-ECU Harness Side Connector Terminal Arrangement
Terminal No.Inspection itemNormal condition (Check condition)
1 – 12No.1 injector2 – 3 Ω (At 20C)
14 – 12No.2 injector
2 – 12No.3 injector
15 – 12No.4 injector
3 – 12Fuel pressure control valve28 – 36 Ω (At 20C)
4 – 12Stepper motor coil (A1)28 – 33 Ω (At 20C)
17 – 12Stepper motor coil (A2)
5 – 12Stepper motor coil (B1)
18 – 12Stepper motor coil (B2)
6 – 12Secondary air control solenoid valve28 – 36 Ω (At 20C)
11 – 12Wastegate solenoid valve62 – 74 Ω (At 20C)
13 – Body earthEngine-ECU earthContinuity established (0 Ω)
26 – Body earth
60 – 12Oxygen sensor heater (EVOLUTION-V
only)11 – 18 Ω (at 20C)
72 – 92Intake air temperature sensor5.3 – 6.7 kΩ (When intake air temperature is 0C)
2.3 – 3.0 kΩ (When intake air temperature is 20C)
1.0 – 1.5 kΩ (When intake air temperature is 40C)
0.30 – 0.42 kΩ (When intake air temperature is 80C)
74 – 77High temperature sensor3 Ω or less
83 – 92Engine coolant temperature sensor5.1 – 6.5 kΩ (When coolant temperature is 0C)
2.1 – 2.7 kΩ (When coolant temperature is 20C)
0.9 – 1.3 kΩ (When coolant temperature is 40C)
0.26 – 0.36 kΩ (When coolant temperature is 80C)
87 – 92Idle position switchContinuity established (when throttle valve is at idle
position)
No continuity (when throttle valve is slightly open)
91 – Body earth–Continuity established

MPI – Troubleshooting13-26
7. INSPECTION PROCEDURE USING
OSCILLOSCOPE
7-1 AIR FLOW SENSOR (AFS)
Observing waveforms displayed on the oscilloscope allows
you to visually identify possible unusual disturbances in
waveform that could temporarily occur in the air flow sensor
output.

(1) Disconnect the air flow sensor connector and connect
the special tool (Test Harness: MB991709) to it. (Ensure
that all terminals are connected.)
(2) Connect the oscilloscope probe to terminal no. 3 of air
flow sensor connector.
NOTE
If the engine ECU connector is used, connect the
oscilloscope probe to terminal no. 90.
(3) Perform the same steps from here on as with the 4G9
engine.
7-2 CAMSHAFT POSITION SENSOR AND CRANK
ANGLE SENSOR
Perform the same steps as with the conventional 4G9 engine
for the inspection.
7-3 INJECTOR
Observing waveforms displayed on the oscilloscope allows
you to visually check the conditions of injector drive signals
actually output from the engine ECU.
Injector Control Signal (Oscilloscope 1)

(1) Disconnect the injector connector and connect the special
tool (Test Harness: MB991348) to the circuit. (Ensure
that the terminals on both the power supply and engine
ECU sides are connected.)
(2) Connect the oscilloscope probe to terminal no. 2 of injector
connector.
NOTE
If the engine ECU connector is used for the measurement,
take measurements at each of the following terminals.
Connect the oscilloscope probe to terminal no. 1 when
the waveform is observed with no. 1 cylinder, to terminal
no. 14 when the waveform is observed with no. 2 cylinder,
to terminal no. 2 when the waveform is observed with
no. 3 cylinder, and to terminal no. 15 when the waveform
is observed with no. 4 cylinder.
Oscilloscope
Oscilloscope

MPI – On-vehicle Service13-32
6. INTAKE AIR TEMPERATURE SENSOR
CHECK
1. Disconnect the air flow sensor connector.
2. Measure resistance between terminals 5 and 6.
Standard value:
2.3 – 3.0 kΩ (at 20C)
0.30 – 0.42 kΩ (at 80C)
3. Measure resistance while heating the sensor using a hair
drier.
Normal condition:
Temperature (C)Resistance (kΩ)
HigherSmaller
4. If the value deviates from the standard value or the
resistance remains unchanged, replace the air flow sensor
assembly.
7. ENGINE COOLANT TEMPERATURE
SENSOR CHECK
The engine coolant temperature sensor is located as shown
on the left.
Standard value:
2.1 – 2.7 kΩ (at 20C)
0.26 – 0.36 kΩ (at 80C)
8. OXYGEN SENSOR CHECK

The sensor connector is located as shown on the left.

(1) Disconnect the oxygen sensor connector and connect
the special tool (Test Harness: MD998464) to the oxygen
sensor connector.
Equipment sideconnector
Air flow sensor
Intake air temperature sensor
Engine coolant
temperature sensor
Oxygen sensor equipment side connector
Oxygen sensor connector
Oxygen sensor

INTAKE AND EXHAUST – On-vehicle Service15-4
3. WASTEGATE ACTUATOR CHECK
(1) Connect a hand pump (pressure type) to the nipple.
(2) Gradually increase the pressure being applied to check
for the pressure at which the wastegate actuator rod starts
moving (approx. 1 mm stroke).
Standard value: Approx. 100 kPa {1.02 kg/cm
2}
Caution
Do not apply a pressure more than 120 kPa {1.23
kg/cm
2} to prevent the diaphragm from being
damaged.
(3) If the pressure drastically deviates from the standard
value, check the actuator or wastegate valve and, if
necessary, replace the actuator or turbocharger assembly.
4. WASTEGATE SOLENOID VALVE CHECK
4-1 OPERATION CHECK
(1) Connect a hand vacuum pump to nipple A of the solenoid
valve.
(2) Using jumper wires, connect the solenoid valve terminal
to battery terminals.
(3) Disconnecting and reconnecting the jumper wire on the
(–) terminal side, apply vacuum to check for airtightness.
Jumper wireNipple B conditionNormally
ConnectedOpenVacuum leaks.
PluggedVacuum retained.
DisconnectedOpenVacuum retained.
4-2 COIL RESISTANCE CHECK
Measure the resistance across solenoid valve terminals.
Standard value: 62 – 74 Ω (at 20
C)
5. AIR BYPASS VALVE CHECK
(1) Remove the air bypass valve.
(2) Connect a hand vacuum pump to the air bypass valve
nipple.
(3) Apply a vacuum of approx. 45 kPa {340 mmHg} and
check that the valve is airtight.
(4) Increase the vacuum and check for valve operation.
VacuumValve operation
Approx. 53 kPa {400 mmHg}Starts moving

INTAKE AND EXHAUST – On-vehicle Service15-5
6. SECONDARY AIR CONTROL SYSTEM
CHECK
(1) Start the engine and let it run at idle speed.
(2) Short-circuit the no. 6 terminal of the engine ECU
connector using a jumper wire and check at this time
that the secondary air valve lifts.
At this time, the engine ECU connector should be
connected.
7. SECONDARY AIR CONTROL SOLENOID
VALVE CHECK
7-1 OPERATION CHECK
(1) Disconnect the vacuum hose (white stripe, yellow stripe)
from the solenoid valve.
(2) Disconnect the harness connector.
(3) Connect a hand vacuum pump to nipple A of the solenoid
valve.
(4) Using jumper wires, connect the solenoid valve terminal
to battery terminals.
(5) Disconnecting and reconnecting the jumper wire on the
(–) terminal side, apply vacuum to check for airtightness.
Jumper wireNipple B conditionNormally
ConnectedOpenVacuum leaks.
PluggedVacuum retained.
DisconnectedOpenVacuum leaks.
7-2 COIL RESISTANCE CHECK
Measure the resistance across solenoid valve terminals.
Standard value: 28 – 36 Ω (at 20
C)
Secondary air control
solenoid valve
Battery