check engine MITSUBISHI LANCER EVOLUTION IV 1998 User Guide

ENGINE – T iming Belt 11-31
(17)Loosen the retaining bolt of the tensioner pulley.
Caution
Loosening the retaining bolt can cause the intake
and exhaust camshafts to turn, resulting in slackened
timing belt. Use care that the timing belt does not
come off the sprockets at this time.
(18)Pull up the slack of the timing belt by turning the tensioner in illustrated direction using the special tool and a torque
wrench (0 – 5 Nm {0 – 0.5 kgf
m}).
(19)From this position, turn back the tensioner until the torque wrench reading becomes 3.5 Nm {0.36 kgf
m}, then
secure it by tightening the retaining bolt.
(20)Remove the special tool attached in step (16).
(21)Rotate the crankshaft clockwise 2 turns. Then, leave it intact 15 minutes.
(22)Check to see that the wire inserted when installing the
auto-tensioner can be pulled out lightly. If it can be pulled
out lightly, the timing belt is being tensioned properly.
If so, remove the wire. In addition, check that the rod
protrusion from the auto-tensioner meets the standard
value, which is also an indication of properly tensioned
timing belt.
Standard value: 3.8 – 4.5 mm
(23)If the wire cannot be removed with a light force, repeat steps (16) through (21) until the proper belt tensioner
is obtained.MD998767

ENGINE – Engine Assembly11-3 5
E ENGINE ASSEMBLY REMOVAL
After checking that all cables, hoses and harness connectors,
etc., are disconnected from the engine, lift the chain block
slowly to remove the engine assembly upward from the engine
compartment.
INSTALLATION SERVICE POINTS
 A ENGINE ASSEMBLY INSTALLATION
Install the engine assembly, checking that the cables, hoses,
and harness connectors are not clamped.
 B ENGINE MOUNT BRACKET INSTALLATION
(1) Place a garage jack against the engine oil pan with a piece of wood in between, and install the engine mount
bracket while adjusting the position of the engine.
(2) Support the engine with the garage jack.
(3) Remove the chain block and support the engine assembly
with the special tools.
 C HIGH-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 bolt to the specification.
MZ203826 or MZ203827
MB991453

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 – Troubleshooting13-8
2. INSPECTION CHART FOR DIAGNOSIS CODES
Code No.Diagnosis itemReference page
12Air flow sensor (AFS) system13-8
13Intake air temperature sensor system13-9
14Throttle position sensor (TPS) system13-9
21Engine coolant temperature sensor system13-10
22Crank angle sensor system13-11
23Camshaft position sensor system13-11
24Vehicle speed sensor system13-12
25Barometric pressure sensor system13-13
31Detonation sensor system13-14
41Injector system13-14
44Ignition coil and power transistor unit system13-15
64Alternator FR terminal system13-16
3. INSPECTION PROCEDURE FOR DIAGNOSIS CODES
Code No. 12 Air flow sensor (AFS) systemProbable cause
Range of Check
Engine speed is 500 r/min or more.
Set conditions
Sensor output frequency is 3 Hz or less for 4 seconds.Malfunction of the air flow sensor
Improper connector contact, open circuit or
short-circuited harness wire of the air flow sensor
Malfunction of the engine-ECU
Measure at the air flow sensor con-
nector A-25.
Connect the connector. (Use
the test harness: MB991709)
1. Voltage between 3 and earth
(Engine: Idling)
OK:2.2–3.2 V
2. Voltage between 7 and earth
OK:0–1 V (Engine: idling)
6–9 V (2,000 r/min)
OK
Replace the engine-ECU.1. NG
Check the air flow sensor circuit.
2. NG
Measure at the engine-ECU con-
nector B-59.
Connect the connector.
Voltage between 19 and earth
(Ignition switch: ON)
OK:6–9 V
OK
Check the following connector:
B-59
OK
Check trouble symptom.
NG
Replace the engine-ECU.NG
Check the following connector:
A-25NG
Repair
OK
Check trouble symptom.
NG
NG
Repair
Replace the air flow sensor.

MPI – Troubleshooting13-9
Code No. 13 Intake air temperature 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.
Set conditions
Sensor output voltage is 4.6 V or more (corresponding to an intake air temperature
of –45C or less) for 4 seconds.
or
Sensor output voltage is 0.2V or less (corresponding to an intake air temperature
of 125C or more) for 4 seconds.Malfunction of the intake air temperature sensor
Improper connector contact, open circuit or
short-circuited harness wire of the intake air
temperature sensor circuit
Malfunction of the engine-ECU
OK
Check trouble symptom.
Check the intake air temperature sen-
sor. (Refer to P.13-32.)NGReplace air flow sensor.
OK
Measure at the air flow sensor connec-
tor A-25.
Disconnect the connector, and
measure at the harness side.
Voltage between 6 and earth
(Ignition switch: ON)
OK:4.5–4.9 V
Continuity between 5 and earth
OK:ContinuityNGCheck the following connector:
C-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between the
engine-ECU and the intake air temper-
ature sensor connector.NG
Repair
OK
Replace the engine-ECU.
OK
Check the following connector:
A-25NG
Repair
NG
Code No. 14 Throttle position sensor (TPS) 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.
Set conditions
The sensor output voltage is 0.2 V or less for 4 seconds.Malfunction of the throttle position sensor
Improper connector contact, open circuit or
short-circuited harness wire of the throttle position
sensor circuit
Improper “ON” state of idle position switch
Short circuit of the idle position switch signal line
Malfunction of the engine-ECU
Check the throttle position sensor.NG
Replace
OK
Measure at the throttle position sensor
connector A-16.
Disconnect the connector, and
measure at the harness side.
Voltage between 1 and earth
(Ignition switch: ON)
OK:4.8–5.2 V
Continuity between 4 and earth
OK:ContinuityNGCheck the following connector:
B-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between the
engine-ECU and the throttle position
sensor connector.NG
Repair
OK
Replace the engine-ECU. OK
Check the throttle position sensor out-
put circuit.

MPI – Troubleshooting13-10
Code No. 21 Engine coolant temperature 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.
Set conditions
Sensor output voltage is 4.6 V or more (corresponding to an engine coolant
temperature of –45C or less) for 4 seconds.
or
Sensor output voltage is 0.1 V or less (corresponding to an engine coolant
temperature of 140C or more) for 4 seconds.Malfunction of the engine coolant temperature sensor
Improper connector contact, open circuit or
short-circuited harness wire of the engine coolant
temperature sensor circuit
Malfunction of the engine-ECU
Range of Check
Ignition switch: ON
Engine speed is approx. 50 r/min or more
Set conditions
The sensor output voltage increases from 1.6 V or less (corresponding to an
engine coolant temperature of 40C or more) to 1.6 V or more (corresponding
to an engine coolant temperature of 40C or less).
After this, the sensor output voltage is 1.6 V or more for 5 minutes.
OK
Check trouble symptom.
Check the engine coolant temperature
sensor. (Refer to P.13-32.)NG
Replace
OK
Measure at the engine coolant temper-
ature sensor connector A-38.
Disconnect the connector, and
measure at the harness side.
Voltage between 1 and earth
(Ignition switch: ON)
OK:4.5–4.9 V
Continuity between 2 and earth
OK:ContinuityNGCheck the following connector:
B-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between the
engine-ECU and the engine coolant
temperature sensor connector.NG
Repair
OK
Replace the engine-ECU.
Check the following connector:
A-38NG OK
Repair
NG

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 – Troubleshooting13-12
Code No. 24 Vehicles speed 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.
Idle position switch: OFF
Engine speed is 3,000 r/min or more.
Driving under high engine load conditions.
Set conditions
Sensor output voltage does not change for 4 seconds (no pulse signal input).Malfunction of the vehicle speed sensor
Improper connector contact, open circuit or
short-circuited harness wire of the vehicle speed
sensor circuit
Malfunction of the engine-ECU
OK
Check the ignition switch. (Refer to GROUP 54 – Ignition Switch.)
2. NG
OK
Replace the engine-ECU.
3. NG
OK
Replace the engine-ECU.
NG
Check the harness wire
between the engine-ECU
and the vehicle speed
sensor connector.NG
Repair
OK
Check trouble symptom.
OK
Check the following
connectors:
A-19, B-62NG
Repair
NG
Check the harness wire
between the engine-ECU
and the vehicle speed
sensor connector.NG
Repair
OK
Check trouble symptom.
Check the following
connector:
B-62NG
Repair
NG
Check the harness wire
between the vehicle
speed sensor and ignition
switch connector.NG
Repair
OK
Check trouble symptom.
OK
Measure at the vehicle speed sensor connector A-19.
Disconnect the connector, and measure at the harness side.
1. Voltage between 1 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 3 and earth (Ignition switch: ON)
OK:4.8 – 5.2 V
3. Continuity between 2 and earth
OK:Continuity1. NGCheck the following
connectors:
B-64, B-74, B-76NG
Repair
Check the vehicle speed sensor. (Refer to GROUP 54 – Combina-
tion Meters.)NG
Replace
Check the harness wire between the vehicle speed sensor and
the earth, and repair if necessary.