Mitsubishi Galant (2004+). Manual - part 1239

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-649

DIAGNOSIS

Required Special Tools:

• MB991958: Scan tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic 
trouble code (DTC).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.

(3) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC P0451 set?

YES : Refer to DTC P0451 - Evaporative Emission Control 

System Pressure Sensor Range/Performance 

P.13B-689

.

NO :  Go to Step 2. 

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-650

STEP 2. Using scan tool MB991958, check data list item 73: 
Fuel Tank Differential Pressure Sensor.

(1) Turn the ignition switch to the "ON" position.
(2) Remove the fuel cap.
(3) Set scan tool MB991958 to the data reading mode for item 

73, Fuel Tank Differential Pressure Sensor.

• The fuel tank differential pressures should be −3.3 to 3.3 

kPa (

−0.97 to 0.97 in.Hg).

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the fuel tank pressure between 

−3.3 to 3.3 kPa (−0.97 

to 0.97 in.Hg)?
YES : Go to Step 3.
NO :  Refer to DTC P0451 - Evaporative Emission Control 

System Pressure Sensor Range/Performance 

P.13B-689

.

STEP 3. Using scan tool MB991958, check actuator test 
item 08: Evaporative Emission Purge Solenoid.

(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool MB991958 to the actuator test mode for item 

08, Evaporative emission purge solenoid.

• An operation sound should be heard and vibration 

should be felt when the evaporative emission purge 
solenoid is operated.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid operating properly?

YES : Go to Step 4.
NO :  Replace the evaporative emission purge solenoid. 

Then go to Step 5.

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-651

STEP 4. Using scan tool MB991958, check actuator test 
item 29: Evaporative Emission Ventilation Solenoid.

(1) Turn the ignition switch to the "ON" position.
(2) Set scan tool MB991958 to the actuator test mode for item 

29, Evaporative emission ventilation solenoid.

• An operation sound should be heard and vibration 

should be felt when the evaporative emission ventilation 
solenoid is operated.

(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the solenoid operating properly?

YES : Repair or replace the vent hose and air filter. Then go 

to Step 5.

NO :  Replace the evaporative emission ventilation 

solenoid. Then go to Step 5.

STEP 5 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 − Procedure 1 − 

Evaporative Emission System Leak Monitor 

P.13B-5

.

(2) Read the diagnostic trouble code.
Q: Is DTC P0441 set?

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

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>

13B-652

DTC P0442: Evaporative Emission System Leak Detected (Small Leak)

.

AC306278

A

B

C

D

E

F

G

O

P

Q

N

M

L

H

I

J

K

AB

INTAKE MANIFOLD PLENUM

FUEL TANK

EVAPORATIVE EMISSION
VENTILATION SOLENOID

CHECK VALVE

EVAPORATIVE EMISSION
PURGE SOLENOID

EVAPORATIVE 
EMISSION CANISTER

ONBOARD REFUELING
VAPOR RECOVERY(ORVR)
VENT VALVE MODULE

SYSTEM DIAGRAM

CHAMBER

AC306400

AB

EVAPORATIVE EMISSION CANISTER

AC306388AB

EVAPORATIVE EMISSION
PURGE SOLENOID 

AC305053AC

EVAPORATIVE EMISSION
VENTILATION SOLENOID