Mitsubishi Eclipse. Manual - part 521

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-627

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 the DTC P0451 is output?

YES : Refer to, DTC P0451 - Evaporative Emission Control 

System Pressure Sensor Range/Performance 

P.13B-673

.

NO :  Go to Step 2. 

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 −1.5 to 1.5 

kPa.

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

YES : Go to Step 3.
NO :  Refer to, DTC P0451 - Evaporative Emission Control 

System Pressure Sensor Range/Performance 

P.13B-673

.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-628

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.

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.

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

AK300810

AB

MB991911

16-PIN

MB991827

MB991824 

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-629

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-7

.)

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

YES : Go to Step 1.
NO :  This diagnosis is complete.

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

AC001944

CHECK VALVE A

CHECK 
VALVE B

EVAPORATIVE 
EMISSION CANISTER

FUEL TANK

EVAPORATIVE 
EMISSION 
VENTILATION 
SOLENOID

EVAPORATIVE EMISSION 
PURGE SOLENOID

INTAKE MANIFOLD

SYSTEM DIAGRAM <VEHICLES WITHOUT INTAKE MANIFOLD TUNING SYSTEM>

B

C

E

F

G

Q

R

I

H

K

J

L

N

O

M

AB

P

A

D

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-630

.

TECHNICAL DESCRIPTION

• To judge if there is leak in the fuel system, ECM 

<M/T> or PCM <A/T> measure the change of the 
pressure inside the fuel tank.

• The ECM <M/T> or PCM <A/T> turns on the 

evaporative emission ventilation solenoid to shot 
off the evaporative emission canister outlet port.

• Then the evaporative emission purge solenoid is 

driven to set the fuel system into a negative pres-
sure.

• When the fuel system develops a vacuum of 2 

kPa (0.29 psi), the evaporative emission purge 
solenoid is turned "OFF" and the fuel system vac-
uum is maintained at 2 kPa (0.29 psi).

AC106496

CHECK VALVE A

CHECK 
VALVE B

EVAPORATIVE 
EMISSION CANISTER

FUEL TANK

EVAPORATIVE 
EMISSION 
VENTILATION 
SOLENOID

EVAPORATIVE EMISSION 
PURGE SOLENOID

INTAKE MANIFOLD

SYSTEM DIAGRAM <VEHICLES WITH INTAKE MANIFOLD TUNING SYSTEM>

B

C

E

F

G

Q

R

I

H

K

J

L

N

O

M

AD

P

AC000183AB

EVAPORATIVE EMISSION CANISTER

FUEL TANK

AC002073AD

EVAPORATIVE EMISSION PURGE 
SOLENOID <VEHICLES WITHOUT 
INTAKE MANIFOLD TUNING SYSTEM>

AC106497

AC

EVAPORATIVE EMISSION PURGE SOLENOID
<VEHICLES WITH INTAKE MANIFOLD TUNING 
SYSTEM>

AIR INTAKE HOSE

AC002035AB

EVAPORATIVE EMISSION 
VENTILATION SOLENOID