Mitsubishi Eclipse. Manual - part 551

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-747

STEP 21. Check for clogging in the evaporator line from 
hose J to hose K.
(1) Remove the fuel tank. (Refer to GROUP 13C, Fuel Tank 

P.13C-13

.)

(2) Disconnect hose J at the liquid separator side, and then 

connect a hand vacuum pump to the hose.

(3) Unplug the hose K at the fuel tank side.
(4) Apply a pressure on the vacuum pump, air should pass 

through the hose K.

(5)
Q: Are the hoses good condition?

YES : Go to Step 22.
NO :  Replace the inferior hose, and reinstall the fuel tank. 

(Refer to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go 

to Step 26.

STEP 22. Check for lclogging in the evaporator line hose I, 
L, M, N and hose O.
(1) Remove the filler neck assembly. (Refer to GROUP 13C, 

Fuel Tank 

P.13C-13

.)

(2) The clogging test with a hand vacuum pump on each hose 

from hoses I, L, M, N and O.

Q: Are the hoses in good condition?

YES : Go to Step 23.
NO :  Replace the inferior hose, and reinstall the filler neck 

assembly. (Refer to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go to Step 26.

AC02040 AB

HOSE J

AC002038 AB

HOSE K

AC002032

AB

HOSE I

AB

AC002039

AB

AB

HOSE O

HOSE L

HOSE N

HOSE M

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-748

STEP 23. Check the check valve A.
(1) Only when you blow the check valve from the direction 

shown, it should pass air.

(2) When you blow the check valve, air should leak from the 

check valve body.

Q: Is check valve A in good condition?

YES : Go to Step 24.
NO :  Replace check valve A, and reinstall the filler neck 

assembly. (Refer to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go to Step 26.

STEP 24. Check the check valve B.
(1) When you blow the check valve from the arrow direction 

shown above, it should pass more air.

(2) When you blow the check valve from the arrow direction 

shown below, it should pass less air.

(3) When you blow the check valve, air should leak from the 

check valve body.

Q: Is check valve B in good condition?

YES : Go to Step 25.
NO :  Replace the chack valve B, and reinstall the filler neck 

assembly. (Refer to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go to Step 26.

AC002039

CHECK VALVE A

AE

AC002076 AB

CHECK VALVE A

AC002039

CHECK VALVE B

AF

AC002078

CHECK VALVE B

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-749

STEP 25. Check for clogging in the evaporator line from 
hose N.
(1) The clogging test with a hand vacuum pump on the hose N.
Q: Is the hose N in good condition?

YES : Go to Step 26.
NO :  Replace the hose N, and reinstall the fuel tank. (Refer 

to GROUP 13C, Fuel Tank 

P.13C-13

.) Then go to 

Step 26.

STEP 26. Test the OBD-II drive cycle.
(1) Confirm the repair by performing the appropriate drive cycle  

(Refer to Diagnostic Function 

− OBD-ll Drive Cycle − 

Procedure 1 

− Evaporative Emission System Leak Monitor 

P.13B-7

). 

(2) Read the diagnostic trouble code.
Q: Is diagnostic trouble code P0455 set?

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

DTC P0456: Evaporative Emission Control System Leak Detected (Very Small Leak)

AC000195

HOSE N

AD

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-750

.

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 valve to 
shot off the evaporative emission canister outlet 
port.

• Then the evaporative emission purge solenoid 

valve is driven to set the fuel system into a nega-
tive pressure.

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