1998 MITSUBISHI LANCER EVOLUTION IV relay

ENGINE – Engine Assembly11- 33
25
27 2819
20 21
22 23
24
26
Unit: Nm {kgf
m}
98 {10.0}*
29
57 {5.8}
22
12 {1.2} 39 {4.0}
9 {0.9}
19. Solenoid valve connector
20. Vacuum tank/solenoid valve/vacuum hose assembly
21. Oil pressure switch connector
22. Alternator connector  Drive belt tension inspection
(Refer to P.11-4.)
 A 23. Drive belt
 B 24. A/C compressor
 C 25. Power steering oil pump
 Transmission assembly 26. A/C relay box
27. A/C receiver bracket mounting bolt
28. Oil pressure hose mounting bolt
 C B 29. Engine mount bracket
 E A 30. Engine assembly
Caution
Mounting locations marked by * should be
provisionally tightened, and then fully tightened after
placing the vehicle horizontally and loading the full
weight of the engine on the vehicle body.

13-1
FUEL
CONTENTS
MULTIPOINT INJECTION (MPI) 2. . . . . . .
GENERAL INFORMATION 2. . . . . . . . . . . . . . . .
SERVICE SPECIFICATIONS 3. . . . . . . . . . . . . .
SEALANT 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 4. . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING 6. . . . . . . . . . . . . . . . . . . .
ON-VEHICLE SERVICE 30. . . . . . . . . . . . . . . .
1. Idle Position Switch and Throttle Position
Sensor (TPS) Adjustment 30. . . . . . . . . . . . .
2. Fixed SAS Adjustment 30. . . . . . . . . . . . . . . .
3. Basic Idle Speed Adjustment 30. . . . . . . . . . 4. Fuel Pressure Measurement 30. . . . . . . . . . .
5. MPI System Components Layout 31. . . . . .
6. Intake Air Temperature Sensor Check 32. .
7. Engine Coolant Temperature
Sensor Check 32. . . . . . . . . . . . . . . . . . . . . . . .
8. Oxygen Sensor Check 32. . . . . . . . . . . . . . . .
9. Injector Check 34. . . . . . . . . . . . . . . . . . . . . . .
10. Resistor Check 34. . . . . . . . . . . . . . . . . . . . . . .
11. Fuel Pump Relay No.2 Check 35. . . . . . . . .
12. Fuel Pump Resistor Check 35. . . . . . . . . . . . INJECTOR 36. . . . . . . . . . . . . . . . . . . . . . . . . . . .
THROTTLE BODY 37. . . . . . . . . . . . . . . . . . . . .

MPI – General Information13-2
MULTIPOINT INJECTION (MPI)
GENERAL INFORMATION
OMPI System Diagram

1 Injector

2 ISC servo

3 Fuel pressure control valve

4 Waste gate solenoid valve

5 Secondary air control solenoid valve
Control relay
Fuel pump relay
A/C relay
Ignition coil
Exhaust temperature warning lamp
Engine warning lamp
Diagnosis output
Alternator G terminal
Fan motor relay
Tachometer
Fuel pump relay No.2 1 Oxygen sensor
2 Air flow sensor
3 Intake air temperature sensor
4 Throttle position sensor
5 Idle switch
6 Camshaft position sensor
7 Crank angle sensor
8 Barometric pressure sensor
9 High temperature sensor
10 Engine coolant temperature sensor
11 Detonation sensor
Power supply voltage
Ignition switch-IG
Ignition switch-ST
Vehicle speed sensor
A/C switch
Power steering fluid pressure switch
Alternator FR signalEngine ECU
1 Oxygen sensor
2 Air flow sensor3
Intake air tem-
perature sensor
4,
5
6 Camshaft position
sensor
7 Crank angle sensor 8 Barometric
pressure sensor
9 High temperature
sensor 10 Coolant temperature sensor
11 Detonation sensor
1 Injector
2 ISC servo

3 Fuel pressure
control valve

4 Waste gate
solenoid valve
5 Secondary air
control solenoid
valveCanister
Check valveFrom
fuel
tank
Throttle position
sensor (with a
built-in
idle
switch)
Secondary
air valve
AirTo fuel
tankFuel
pressure
regulatorFrom
fuel
pump
Waste gate
actuator
Catalytic converter
Given above is the MPI system diagram for EVOLUTION-IV. The MPI system for EVOLUTION-V is different
from this in the following point;
Oxygen sensor with a heater is adopted.
The diagnosis connector power supply circuit is different.
The high temperature sensor is no longer used.

MPI – Troubleshooting13-6
TROUBLESHOOTING
1. DIAGNOSIS FUNCTION
1-1 ENGINE WARNING LAMP (CHECK ENGINE LAMP)
If an abnormality occurs in any of the following items related
to the Multipoint Fuel Injection (MPI) system, the engine
warning lamp will illuminate.
If the lamp remains illuminated or if the lamp illuminates while
the engine is running, check the diagnosis code output.
Engine warning lamp inspection items
Engine-ECU
Air flow sensor (AFS)
Intake air temperature sensor
Throttle position sensor (TPS)
Engine coolant temperature sensor
Crank angle sensor
Camshaft position sensor
Barometric pressure sensor
Detonation sensor
Injector
Ignition coil, power transister
Misfire
1-2 METHOD OF READING AND ERASING DIAGNOSIS
CODES
(1) Use the special tool to earth No.1 terminal (diagnosis
control terminal) of the diagnosis connector.
(2) To check ABS system, remove the valve relay.
NOTE
That is because the valve relay is off and the warning
lamp remains illuminated if there is a fault in the ABS
system.
(3) Turn off the ignition switch.
(4) Read out a diagnosis code by observing how the warning
lamp flashes.
Indication of diagnosis code by warning lamp
When the diagnosis code No.24 is outputWhen no diagnosis code is output*
On
Off
1.5 secs.0.5 sec.
0.5 sec.
Pause
time 3
secs.Tens signalPlace
division
2 secs.Units signal
A03X0113
On
Off
0.5 sec.
0.25 sec.
NOTE
*: Even if the ABS system is normal, removing the valve relay causes the diagnosis code No.52 to
be output.
Engine warning lamp
(check engine lamp)

MPI – Troubleshooting13-11
Code No. 22 Crank angle sensor systemProbable cause
Range of Check
Engine is cranking.
Set conditions
Sensor output voltage does not change for 4 seconds (no pulse signal input.)Malfunction of the crank angle sensor
Improper connector contact, open circuit or
short-circuited harness wire of the crank angle sensor
Malfunction of the engine-ECU
Measure at the crank angle sensor connector A-51.
Connect the connector. (Use the test harness: MD998478.)
Voltage between 2 (black clip) and earth (Engine: cranking)
OK:0.4–4.0 V
Voltage between 2 (black clip) and earth (Engine: idling)
OK:1.5–2.5 V
NGOKReplace the engine-ECU.
Measure at the crank angle sensor connector A-51.
Disconnect the connector, and measure at the harness side.
1. Voltage between 3 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 2 and earth (Ignition switch: ON)
OK:4.8–5.2 V
3. Continuity between 1 and earth
OK:Continuity
OK
Check the following con-
nector: A-51NG
Repair
OK
Check trouble symptom.
NG
Replace the crank angle sensor.1. NG
Check the harness wire between the crank angle sensor and the
control relay connector, and repair if necessary.
2. NGCheck the following con-
nector: B-62NG
Repair
OK3. NG
Check trouble symptom.
NG
Check the harness wire
between the engine-ECU and
the crank angle sensor
connector.NG
Repair
OK
Replace the engine-ECU.
Check the harness wire between the crank angle sensor and the
earth, and repair if necessary.
Code No. 23 Camshaft position sensor systemProbable cause
Range of Check
Ignition switch: ON
Engine speed is approx. 50 r/min or more.
Set conditions
Sensor output voltage does not change for 4 seconds (no pulse signal input.)Malfunction of the camshaft position sensor
Improper connector contact, open circuit or
short-circuited harness wire of the camshaft position
sensor circuit
Malfunction of the engine-ECU
Measure at the camshaft position sensor connector A-97.
Connect the connector.
Voltage between 2 and earth (Engine: cranking)
OK:0.4–3.0 V
Voltage between 2 and earth (Engine: idling)
OK:0.5–2.0 VOKReplace the engine-ECU.
NG
Measure at the camshaft position sensor connector A-97.
Disconnect the connector, and measure at the harness side.
1. Voltage between 3 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 2 and earth (Ignition switch: ON)
OK:4.8–5.2 V
3. Continuity between 1 and earth
OK:Continuity1. NGCheck the harness wire between the camshaft position sensor
and the control relay connector, and repair if necessary.
2. NGCheck the following con-
nector: B-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between the engine-ECU and
the camshaft position sensor
connector.NG
Repair
OK
Replace the engine-ECU. 3. NG
Check the harness wire between the camshaft position sensor
and the earth, and repair if necessary.
OK
Check the following con-
nector: A-97NG
Repair
OK
Check trouble symptom.
NG
Replace the camshaft position sensor.

MPI – Troubleshooting13-14
Code No.31 Detonation sensor systemProbable cause
Range of Check
Ignition switch: ON
Excluding 60 seconds after the ignition switch is turned to ON or immediately
after the engine starts.
Engine speed is approx. 5,000 r/min or more
Set conditions
The change in the detonation sensor output voltage (detonation sensor peak voltage
at each 1/2 revolution of the crankshaft) is less than 0.06 V for 200 times in succession.Malfunction of the detonation sensor
Improper connector contact, open circuit or
short-circuited harness wire of the detonation sensor
circuit
Malfunction of the engine-ECU
Measure at the detonation sensor con-
nector A-96.
Disconnect the connector and
measure at the harness side.
Continuity between 2 and earth
OK:ContinuityOKCheck the following connector:
B-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between the
engine-ECU and the detonation sensor
connector.OKReplace the detonation sensor.
Check trouble symptom.
NG
Replace the engine-ECU.
NG
Repair
NG
Check the harness wire between the
detonation sensor and earth, and repair
if necessary.
Code No. 41 Injector systemProbable cause
Range of Check
Engine speed is approx. 50–1,000 r/min
The throttle position sensor output voltage is 1.15 V or less.
Set conditions
Surge voltage of injector coil is not detected for 4 seconds.Malfunction of the injector
Improper connector contact, open circuit or
short-circuited harness wire of the injector circuit
Malfunction of the engine-ECU
NG
Check the harness wire between the
resistor and the injector connector, and
repair if necessary.
OK
Check trouble symptom.
OK
Check the injector control circuit.
OK
Measure at the injector connectors
A-53, A-54, A-55, A-56.
Disconnect the connector, and
measure at the harness side.
Voltage between 1 and earth
(Ignition switch: ON)
OK:System voltageNGCheck the following connector:
A-125NG
Repair
Check the injector. (Refer to P.13-34.)
Check the resistor. (Refer to P.13-34.)NG
Replace
OK
Measure at the resistor connector
A-125.
Disconnect the connector, and
measure at the harness side.
Voltage between 3 and earth
(Ignition switch: ON)
OK:System voltageNGCheck the harness wire between the
control relay and the resistor connec-
tor, and repair if necessary.

MPI – Troubleshooting13-20
Item
No.Normal condition Inspection contents Inspection
item
41Injector
drive time*2Engine: CrankingWhen engine coolant temper-
ature is 0C (injection is
carried out for all cylinders
simultaneously)27 – 41 ms
When engine coolant temper-
ature is 20C14 – 22 ms
When engine coolant temper-
ature is 80C3.9 – 5.9 ms
Injector
drive time*3Engine coolant temperature:
8095C
Engine is idling1.2 – 2.4 ms
drive time*380 – 95C
Lamps, electric cooling fan and
all accessories: OFF
2,500 r/min1.0 – 2.2 ms
all accessories: OFF
Transmission: NeutralWhen engine is suddenly
racedIncreases
44Ignition
advanceEngine: After having been
warmed up
Timing lamp is set (The timing
Engine is idling3 – 13BTDC
Timing lamp is set. (The timing
lamp is set in order to check
actual ignition timing.)2,500 r/min24 – 44BTDC
45ISC
(stepper)
motor
Engine coolant temperature:
80 – 90C
Lamps electric coolingfan and
A/C switch: OFF2 – 25 steps
motor
position *4Lamps, electric cooling fan and
all accessories: OFF
Transmission: Neutral
Idle position switch: ON
Engine: Idling
A/C switch: OFF → ONIncreases by 10 – 70
steps
Engine: Idling
(When A/C switch is ON, A/C
compressor should be operat-
ing.)A/C switch: OFFIncreases by 5 – 50
steps
49A/C relayEngine: After having been warmed
up/Engine is idlingA/C switch: OFFOFF (Compressor
clutch is not operating)
A/C switch: ONON (Compressor
clutch is operating)
NOTE
*1: The idle position switch normally turns off when the voltage of the throttle position sensor is 50 – 100 mV
higher than the voltage at the idle position. If the idle position switch turns back on after the throttle valve
is opened, the idle position switch and the throttle position sensor need to be adjusted.
*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.
*4: In a new vehicle [driven approximately 500 km or less], the step of the stepper motor is sometimes 30 steps
greater than the standard value.

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