1998 MITSUBISHI LANCER EVOLUTION IV sensor

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.

MPI – Troubleshooting13-13
Code No. 25 Barometric pressure 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 4.5 V or more (corresponding to a barometric pressure
of 114 kPa {855 mmHg} or more) for 4 seconds.
or
Sensor output voltage is 0.2 V or less (corresponding to a barometric pressure
of 53 kPa {40 mmHg} or less) for 4 seconds.Malfunction of the barometric pressure sensor
Improper connector contact, open circuit or
short-circuited harness wire of the barometric pressure
sensor circuit
Malfunction of the engine-ECU
OK
Replace the air flow sensor.
Measure at the air flow sensor con-
nector A-25.
Connect the connector. (Use
the test harness: MB991709)
Voltage between 2 and earth
(Ignition switch: ON)
OK:3.7–4.3 V (Altitude: 0 m)
3.2–3.8 V
(Altitude: 1,200 m)NGMeasure at the air flow sensor con-
nector A-25.
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 5 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 baromet-
ric pressure sensor connector.NG
Repair
OK
Replace the engine-ECU.
OK
Check the following connector:
A-25NG
Repair
OK
Check trouble symptom.Check the harness wire between
the engine-ECU and the baromet-
ric pressure sensor connector.NG
Repair
OK
Measure at the engine-ECU con-
nector B-62.
Connect the connector.
Voltage between 85 and earth
(Ignition switch: ON)
OK:3.7–4.3 V (Altitude: 0 m)
3.2–3.8 V
(Altitude: 1,200 m)NGCheck the harness wire between
the engine-ECU and the baromet-
ric pressure sensor connector, and
repair if necessary.
Check the following connec-
tors:
A-25, B-62
OK
Check trouble symptom.
NG
Replace the engine-ECU.NG
Repair OKNG

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 – Troubleshooting13-15
Code No. 44 Ignition coil and power transistor unit systemProbable cause
Range of Check
Engine speed is approx. 50 – 4,000 r/min.
Engine is not being cranked.
Set conditions
Abnormal engine speed is detected due to misfiring by crank angle sensor. (One
of two coils fails.)Malfunction of the ignition coil
Improper connector contact, open circuit or
short-circuited harness wire of the ignition primary
circuit
Malfunction of the engine-ECU.
NG
Check the harness wire between the ignition coil and ignition switch
connector, and repair if necessary.
2. NG
OK
Replace the engine-ECU.
3. NG
NG
Check the following items.
Check the spark plugs and spark plug cables.
Check the compression pressure.
OK
Check trouble symptom.
OK
Check the following
connectors:
A-110, A-111NG
Repair
NG
Check the harness wire
between the engine-ECU
and ignition coil connec-
tor.NG
Repair
OK
Check trouble symptom.
Check the following
connector:
B-59NG
Repair
OK
Check trouble symptom.
OK
Measure at the ignition coil connectors A-110, A-111.
Disconnect the connector, and measure at the harness.
1. Voltage between 1 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 3 and earth (Engine: Cranking)
OK:0.5 – 4.0 V
3. Continuity between 2 and earth
OK:Continuity1. NGCheck the following
connectors:
B-65, B-76NG
Repair
Check the ignition coil. (Refer to Group 16 – Ignition System.)NG
Replace
Check the harness wire between the ignition coil connector and
earth, and repair if necessary.

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 – Troubleshooting13-19
Item
No.Inspection
itemInspection contentsNormal condition
21Engine
coolant
temperature
Ignition switch: ON or with engine
runningWhen engine coolant temper-
ature is –20C–20C
temperature
sensorWhen engine coolant temper-
ature is 0C0C
When engine coolant temper-
ature is 20C20C
When engine coolant temper-
ature is 40C40C
When engine coolant temper-
ature is 80C80C
22Crank angle
sensorEngine: Idling
Idle position switch: ONWhen engine coolant temper-
ature is –20C1,300 – 1,500 rpm
When engine coolant temper-
ature is 0C1,300 – 1,500 rpm
When engine coolant temper-
ature is 20C1,300 – 1,500 rpm
When engine coolant temper-
ature is 40C1,150 – 1,350 rpm
When engine coolant temper-
ature is 80C750 – 950 rpm
25Barometric
pressure
Ignition switch: ONAt altitude of 0 m101 kPa
pressure
sensor
At altitude of 600 m95 kPa
At altitude of 1,200 m88 kPa
At altitude of 1,800 m81 kPa
26Idle position
switchIgnition switch: ON
(Check by operating accelerator
dl tdl )
Throttle valve: Set to idle
positionON
pedal repeatedly.)Throttle valve: Slightly openOFF*1
27Power
steering fluidEngine: IdlingSteering wheel stationaryOFF
tg
pressure
switchSteering wheel turningON
28A/C switchEngine: Idling
(when A/C switch is ON A/C
A/C switch: OFFOFF
(when A/C switch is ON, A/C
compressor should be operating.)A/C switch: ONON

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.