Mitsubishi Lancer Evolution X. Manual - part 345

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-445

STEP 3. Check the evaporative emission ventilation 
solenoid.
(1) Disconnect the evaporative emission ventilation solenoid 

connector F-23.

(2) Measure the resistance between evaporative emission 

ventilation solenoid side connector terminal No. 1 and No. 
2.

Standard value: 17 − 21 Ω [at 20° C (68° F)]

Q: Is the measured resistance between 17 and 21 Ω [at 

20° C (68° F)]?
YES : Go to Step 4.
NO :  Replace it. Then go to Step 10.

STEP 4. Measure the power supply voltage at evaporative 
emission ventilation solenoid harness side connector 
F-23.
(1) Disconnect the connector F-23 and measure at the harness 

side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal No. 2 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 6.
NO :  Go to Step 5.

STEP 5. Check harness connector A-34X at MFI relay for 
damage.
Q: Is the harness connector in good condition?

YES : Check harness connectors C-43, C-47 and D-16 at 

intermediate connectors for damage, and repair or 
replace as required. Refer to GROUP 00E, Harness 
Connector Inspection 

P.00E-2

. If intermediate 

connectors are in good condition, repair harness wire 
between MFI relay connector A-34X (terminal No. 2) 
and evaporative emission ventilation solenoid 
connector F-23 (terminal No. 2) because of open 
circuit or short circuit to ground. Then go to Step 10.

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 10.

1 2

AK202969

Evaporative emission 
ventilation solenoid 
connector

AC

1

2

AK202972

F-23 harness 
connector: 
component side

AF

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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STEP 6. Check harness connector B-10 at ECM for 
damage.
Q: Is the harness connector in good condition?

YES : Go to Step 7.
NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 10.

STEP 7. Measure the power supply voltage at ECM 
connector B-10 by using power plant ECU check harness 
special tool MB992110.
(1) Disconnect all ECM connectors. Connect the power plant 

ECU check harness special tool MB992110 between the 
separated connectors.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 117 and ground.

• Voltage should be battery positive voltage.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 8.
NO :  Check harness connectors C-47 and D-16 at 

intermediate connectors for damage, and repair or 
replace as required. Refer to GROUP 00E, Harness 
Connector Inspection 

P.00E-2

. If intermediate 

connectors are in good condition, repair harness wire 
between evaporative emission ventilation solenoid 
connector F-23 (terminal No. 1) and ECM connector 
B-10 (terminal No. 117) because of open circuit or 
short circuit to ground. Then go to Step 10.

AK604171

ECM

AB

Body side harness 

MB992110

82 81 80 79 78 77 76 75 74 73 72 71

94 93 92 91 90 89 88 87 86 85 84 83

99 98 97 96 95

100

101

102

103

104

105

106

112

113

114

109 108

107

110

111

115

116

117

118

AK604210 AB

Power plant ECU
check harness connector

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-447

STEP 8. Check for harness damage between MFI relay 
connector A-34X (terminal No. 2) and evaporative emission 
ventilation solenoid connector F-23 (terminal No. 2).
NOTE: Check harness after checking intermediate connectors 
C-43, C-47 and D-16. If intermediate connectors are damaged, 
repair or replace them. Refer to GROUP 00E, Harness Con-
nector Inspection 

P.00E-2

. Then go to Step 10.

Q: Is the harness wire in good condition?

YES : Go to Step 9.
NO :  Repair it. Then go to Step 10.

STEP 9. Check for harness damage between evaporative 
emission ventilation solenoid connector F-23 (terminal No. 
1) and ECM connector B-10 (terminal No. 117).
NOTE: Check harness after checking intermediate connectors 
C-47 and D-16. If intermediate connectors are damaged, repair 
or replace them. Refer to GROUP 00E, Harness Connector 
Inspection 

P.00E-2

. Then go to Step 10.

Q: Is the harness wire in good condition?

YES : Replace the ECM. When the ECM is replaced, 

register the ID code. Refer to GROUP 42B, ID Code 
Registration Necessity Judgment Table <Vehicles 
with KOS> 

P.42B-11

 or GROUP 42C, ID Codes 

Registration Judgment Table <Vehicles with WCM> 

P.42C-9

. Then go to Step 10.

NO :  Repair it. Then go to Step 10.

STEP 10. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to 

Diagnostic Function − OBD-II Drive Cycle − Pattern 23 

P.13A-9

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0446 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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DTC P0450: Evaporative Emission Control System Pressure Sensor Malfunction

AK704684

L

A

B

C

D

E

F

H

G

I

J

K

AB

Intake manifold

Fuel tank

Check valve

Evaporative emission
purge solenoid

Evaporative emission
ventilation solenoid

Evaporative emission
canister

Fuel tank differential 
pressure sensor

System diagram

Air filter

Vent pipe