1999 MITSUBISHI LANCER EVOLUTION VI Workshop Manual

MPI – Troubleshooting13-49
INSPECTION PROCEDURE 41
MUT-II: Check if idling speed is unstable.
OK
MUT-II Data list
45 ISC servo position (Refer to P.13-60.)NGAdjust the basic idle speed. (Refer to P.13-30.)*
MUT-II Data list
28 A/C switch (Refer to P.13-58.)NGCheck the A/C switch and A/C relay system.
(Refer to P.13-39. INSPECTION PROCEDURE 29.)
OK
OK
MUT-II Data list
27 Power steering fluid pressure switch (Refer to P.13-58)NGCheck the power steering fluid pressure switch system.
(Refer to P.13-39, INSPECTION PROCEDURE 28.)
1. Inspect the intake of air into the air intake system.

Broken intake manifold gasket

Broken vacuum hose

PCV valve does not operate.

Broken air intake hose
2. Check the injector for clog.
OK
OK
MUT-II Data list
11 Oxygen sensor
OK:Changes between 0–400 mV and 600–1,000 mV during
idlingNGCheck the fuel pressure. (Refer to P.13-30.)*
OK
MUT-II Data list
11 Oxygen sensor
OK:600–1,000 mV during sudden racingNGCheck the oxygen sensor system. (Refer to P.13-42, INSPECTION
PROCEDURE 31.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-21.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
25 Barometric pressure sensor (Refer to P.13-58.)NGCheck the barometric pressure sensor system. (Refer to P.13-14,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 25.)
OK
MUT-II Data list
13 Intake air temperature sensor (Refer to P.13-56.)NGCheck the intake air temperature sensor system. (Refer to P.13-9,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 13.)
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).

MPI – Troubleshooting13-50
INSPECTION PROCEDURE 42
MUT-II: Engine stalling inspection when the engine is warmed up and idling.
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
MUT-II Data list
13 Intake air temperature sensor (Refer to P.13-56.)NGCheck the intake air temperature sensor system. (Refer to P.13-9,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 13.)
OK
MUT-II Data list
25 Barometric pressure sensor (Refer to P.13-58.)NGCheck the barometric pressure sensor system. (Refer to P.13-14,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 25.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
11 Oxygen sensor
OK:600–1,000 mV during sudden racingNGCheck the oxygen sensor system. (Refer to P.13-42, INSPECTION
PROCEDURE 31.)
OK
MUT-II Data list
11 Oxygen sensor
OK:Changes between 0–400 mV and 600–1,000 mV during
idlingNGCheck the fuel pressure. (Refer to P.13-30.)*
OK
MUT-II Data list
27 Power steering fluid pressure switch (Refer to P.13-58.)NGCheck the power steering fluid pressure switch system.
(Refer to P.13-39, INSPECTION PROCEDURE 28.)
OK
MUT-II Data list
28 A/C switch (Refer to P.13-58.)NGCheck the A/C switch and A/C relay system.
(Refer to P.13-39, INSPECTION PROCEDURE 29.)
OK
MUT-II Data list
45 ISC servo position (Refer to P.13-60.)NGAdjust the basic idle speed. (Refer to P.13-30.)*
1. Inspect the intake of air into the air intake system

Broken intake manifold gasket

Broken vacuum hose

PCV valve does not operate.

Broken air intake hose
2. Check the injector for clog.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).

MPI – Troubleshooting13-51
INSPECTION PROCEDURE 43
MUT-II: Check if hesitation, sag, stumble or poor acceleration occurs.
OK
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
MUT-II Data list
13 Intake air temperature sensor (Refer to P.13-56.)NGCheck the intake air temperature sensor system. (Refer to P.13-9,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 13.)
OK
MUT-II Data list
25 Barometric pressure sensor (Refer to P.13-58.)NGCheck the barometric pressure sensor system. (Refer to P.13-14,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 25.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
14 Throttle position sensor (Refer to P.13-57.)NGCheck the throttle position sensor system. (Refer to P.13-9, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE 14.)
OK
MUT-II Actuator test
12 Waste gate solenoid valve (Refer to P.13-61.)NGCheck the waste gate solenoid valve system.
(Refer to P.13-45, INSPECTION PROCEDURE 35.)
OK
MUT-II Data list
11 Oxygen sensor
OK:Changes between 600–1,000 mV during sudden racingNGCheck the oxygen sensor system. (Refer to P.13-42, INSPECTION
PROCEDURE 31.)
OK
MUT-II Data list
11 Oxygen sensor
OK:Changes between 0–400 mV and 600–1,000 mV during
idlingNGCheck the fuel pressure. (Refer to P.13-30.)*
OK
MUT-II Actuator test
09 Fuel pressure control valve (Refer to P.13-61.)NGCheck the fuel pressure control valve system.
(Refer to P.13-45, INSPECTION PROCEDURE 34.)
1. Inspect the intake of air into the air intake system

Broken intake manifold gasket

Broken vacuum hose

PCV valve does not operate.

Broken air intake hose
2. Check the injector for clog.
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).

MPI – Troubleshooting13-52
INSPECTION PROCEDURE 44
MUT-II: Check if surge occurs.
MUT-II Data list
26 Idle position switch (Refer to P.13-58.)NGCheck the idle position switch system.
(Refer to P.13-38, INSPECTION PROCEDURE 26.)
OK
MUT-II Data list
13 Intake air temperature sensor (Refer to P.13-56.)NGCheck the intake air temperature sensor system. (Refer to P.13-9,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 13.)
OK
MUT-II Data list
25 Barometric pressure sensor (Refer to P.13-58.)NGCheck the barometric pressure sensor system. (Refer to P.13-14,
INSPECTION PROCEDURE FOR DIAGNOSIS CODE 25.)
OK
MUT-II Data list
21 Engine coolant temperature sensor (Refer to P.13-57.)NGCheck the engine coolant temperature sensor system.
(Refer to P.13-10, INSPECTION PROCEDURE FOR DIAGNOSIS
CODE 21.)
OK
MUT-II Data list
14 Throttle position sensor (Refer to P.13-57.)NGCheck the throttle position sensor system. (Refer to P.13-9, IN-
SPECTION PROCEDURE FOR DIAGNOSIS CODE 14.)
OK
MUT-II Data list
11 Oxygen sensor
OK:600–1,000 mV during sudden racingNGCheck the oxygen sensor system.
(Refer to P.13-42, INSPECTION PROCEDURE 31.)
OK
MUT-II Data list
11 Oxygen sensor
OK:Changes between 0–400 mV and 600–1,000 mV during
idlingNGCheck the fuel pressure. (Refer to P.13-30.)*
1. Inspect the intake of air into the air intake system

Broken intake manifold gasket

Broken vacuum hose

PCV valve does not operate.

Broken air intake hose
2. Check the injector for clog.OK
NOTE
*: Refer to Workshop Manual for LANCER EVOLUTION-IV and EVOLUTION-V (Pub. No. S9806CNCP9).

MPI – Troubleshooting13-53
INSPECTION PROCEDURE 45
Check the engine-ECU power supply and earth circuit.
Measure at the engine-ECU connectors, B-59, B-60, B-62.

Disconnect the connector and measure at the harness side
1. Voltage between 82 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 38 and earth
OK:System voltage
3. Voltage between 12, 25 and earth (Ignition switch: ON)
OK:System voltage (when the terminal 38 is earthed)
4. Continuity between 13, 26 and earth
OK:Continuity
5. Voltage between 80 and earth
OK:System voltage1. NGCheck the following
connectors: B-65, B-76NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between engine-ECU and
ignition switch connector.NG
Repair
OK
Check the ignition switch. (Refer to GROUP 54.)
2, 3. NG
4. NG
Check the harness wire between engine-ECU and earth, and repair
if necessary.
5. NG
OK
Check the following
connectors:
B-59, B-60, B-62NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
Check the following connectors:
B-65, B-49, B-75, B-73NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between engine-ECU and battery, and
repair if necessary.
Check the harness wire between engine-ECU and control relay
connector, and repair if necessary.
INSPECTION PROCEDURE 46
Check fuel pump circuit.
Measure at the fuel pump connector D-18.

Disconnect the connector and measure at the harness side.

Continuity between 1 and earth
OK:ContinuityNGCheck the following connector:
D-04NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between fuel pump and earth, and repair
if necessary.
OK
Check the following connectors: D-04, B-64NG
Repair OKCheck trouble symptom.
NG
Check the harness wire between terminal for fuel pump drive and
fuel pump connector.NG
Repair
OK
Replace the fuel pump.

MPI – Troubleshooting13-54
INSPECTION PROCEDURE 46
Check fuel pump circuit.
Measure at the fuel pump relay connector D-18.

Disconnect the connector and measure at the harness side.

Continuity between 1 and earth
OK:ContinuityNGCheck the following connector:
D-04NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between fuel pump and earth, and repair
if necessary.
OK
Check the following connectors: A-123, B-64, D-18, D-32NG
Repair OKCheck trouble symptom.
NG
Check the harness wire between fuel pump and fuel pump relay
No.2 connector.NG
Repair
OK
Replace the fuel pump.
INSPECTION PROCEDURE 47
Check the fuel pump drive control circuit.
NG
Check the harness wire between the fuel pump relay and engine-
ECU connector.
OK
Check trouble symptom.
OK
Check trouble symptom.
NG
Check the harness wire
between fuel pump relay
and ignition switch con-
nector.NG
Repair
OK
Check the ignition switch. (Refer to GROUP 54.)OK
Check trouble symptom.
NG
Replace the engine-ECU.
NG
Repair
OK
Check the following connector: B-59
OK
Measure at the engine-ECU connector B-59.

Disconnect the connector and measure at the harness side.

Voltage between 8 and earth (Ignition switch: ON)
OK:System voltageNG
Measure at the fuel pump relay connector B-28.

Disconnect the connector and measure at the harness side.

Voltage between 3, 4 and earth (Ignition switch: ON)
OK:System voltageNGCheck the following
connectors: B-65, B-76NG
Repair
Check the following
connector: B-28NG
Repair

MPI – TroubleshootingMPI – Troubleshooting13-55
INSPECTION PROCEDURE 48
Check air flow sensor control circuit.
2, 3. NGCheck the following
connector: B-62NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between the engine-ECU
and air flow sensor con-
nector.NG
Repair
OK
Replace the engine-ECU.
OK
Check trouble symptom.
NG
Replace the air flow sensor.
NG
Repair
OK
Check the following connector: A-25
Measure at the air flow sensor connector A-25.

Disconnect the connector and measure at the harness side.
1. Voltage between 4 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 5 and earth
OK:Continuity1. NGCheck the harness wire between the air flow sensor and control
relay connector, and repair if necessary.
INSPECTION PROCEDURE 49
Check throttle position sensor output circuit.
Measure at the engine-ECU connector B-62.

Connect the connector.

Voltage between 84 and earth (Ignition switch: ON)
OK:0.3–1.0 V (Throttle valve at idle position)
4.5–5.5 V (Throttle valve fully open)NGCheck the following
connector: B-62NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
OK
Check the harness wire between engine-ECU and throttle position
sensor connector, and repair if necessary.
INSPECTION PROCEDURE 50
Check injector control circuit.
Measure at the engine-ECU connector B-59.

Disconnect the connector and measure at the harness side.

Voltage between 1, 2, 14, 15 and earth (Ignition switch: ON)
OK:System voltageNGCheck the following
connectors:
A-53, A-54, A-55, A-56NG
Repair
OK
Check trouble symptom.
NG
Check the harness between engine-ECU and injector connector,
and repair if necessary.
OK
Check the following connector: B-59
OK
Check trouble symptom.
NG
Replace the engine-ECU.NG
Repair

MPI – Troubleshooting13-56
DATA LIST REFERENCE TABLE
Item
No.Inspection
itemInspection contentsNormal conditionInspection
procedure
No.Reference
page
11Oxygen
sensorEngine:After having
warmed up
Air/fuel mixture is
made leaner when de-
When at 4,000 r/min,
engine is suddenly
decelerated200 mV or lessProcedure
No. 3113-42
made leaner when de-
celerating, and is made
richer when racing.
When engine is
suddenly raced600 – 1,000 mV
Engine:After having
warmed up
The oxygen sensor
si
gnal is used to check
Engine is idling400 mV or less
(Changes)
signal is used to check
the air/fuel mixture
ratio, and control
condition is also
checked by the ECU.2,500 r/min600 – 1,000 mV
12Air flow
sensor*
Engine coolant
tem
perature: 80 –
Engine is idling17 – 43 Hz––
sensor
TION-IV>temperature: 80
95C

Lamps, electric
li f d ll
2,500 r/min46 – 86 Hzp
cooling fan and all
accessories: OFF

Transmission:
Neutral (A/T:
P range)Engine is racedFrequency
increases in
response to
racing
12Air flow
sensor*
Engine coolant
tem
perature: 80 –
Engine is idling12 – 38 Hz––
sensor
TION-V, VI>temperature: 80
95C

Lamps, electric
li f d ll
2,500 r/min36 – 76 Hzp
cooling fan and all
accessories: OFF

Transmission:
Neutral (A/T:
P range)Engine is racedFrequency
increases in
response to
racing
13Intake air
temperature
sensor
Ignition switch: ON or
with engine runningWhen intake air
temperature is –20C–20CCode No.
1313-9
sensorWhen intake air
temperature is 0C0C
When intake air
temperature is 20C20C
When intake air
temperature is 40C40C
When intake air
temperature is 80C80C
NOTE
*: In a new vehicle [driven approximately 500 km or less], the air flow sensor output frequency is sometimes
10% higher than the standard frequency.