Mitsubishi Montero Sport (2004+). Manual - part 298

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-605

DTC P0455: Evaporative Emission Control System Leak Detected (Gross Leak)

.

AC005137

AB

A

Q

O

N

P

B

C

M*

M*

E

A

D

M

E

L

K

F

G

I

H

FUEL TANK

EVAPORATIVE
EMISSION
CANISTER

EVAPORATIVE
EMISSION
PURGE SOLENOID

EVAPORATIVE
EMISSION
VENTILATION
SOLENOID

CHECK VALVE A

CHECK VALVE B

INTAKE MANIFOLD

SYSTEM DIAGRAM

J

VENT VALVE MODULE

NOTE
*: Manifold port

FUEL TANK DIFFERENTIAL
PRESSURE SENSOR

ACX01347AB

EVAPORATIVE EMISSION
PURGE SOLENOID

AC004938AB

EVAPORATIVE EMISSION
VENTILATION SOLENOID

AC005146

EVAPORATIVE EMISSION CANISTER

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-606

TECHNICAL DESCRIPTION

• The fuel tank may be under a slight positive and 

negative pressure depending on the state of the 
evaporative emission system. The PCM monitors 
and responds to these pressure changes. If the 
pressure varies from the specified range, the 
PCM will set DTC P0455.

• The PCM energizes the evaporative emission 

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

• The evaporative emission purge solenoid is to 

apply engine manifold vacuum to the evaporative 
emission system.

• 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).

• The PCM determines if there is a leak or clog in 

the fuel system by measuring the change of vac-
uum inside the fuel tank.

• The test is stopped when fuel vapor pressure is 

determined to be too high.

.

DESCRIPTIONS OF MONITOR METHODS

• Depressurizing EVAP system by intake manifold 

negative pressure is impossible within specified 
period.

.

MONITOR EXECUTION

• Once per driving cycle.

.

MONITOR EXECUTION CONDITIONS (Other 
Monitor and Sensor)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• Evaporative emission purge solenoid monitor

• Evaporative emission purge system monitor

• Fuel tank differential pressure sensor monitor

• Evaporative emission ventilation solenoid monitor

• Fuel level sensor monitor

• Fuel temperature sensor monitor

 Sensor (The sensors below are determined to be 

normal)

• Volume airflow sensor

• Barometric pressure sensor

• Intake air temperature sensor

• Engine coolant temperature sensor

.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-607

LOGIC FLOW CHARTS (Monitor Sequence)

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AC306649

0.04in, 0.02in GROSS LEAK MONITOR

START

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

MONITORING
CONDITIONS?

DEPRESSURIZE FUEL TANK PRESSURE

GROSS LEAK

MONITORING CONDITIONS

SHUT PURGE LINE

MEASURE REVERTING
PRESSURE :    PFT

PFT > PT

SPECIFIED TIMES

MONITORED

MALFUNCTION

END

SPECIFIED TIMES

HAVE PASSED

MALFUNCTION

(GROSS LEAK)

GOOD

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-608

DTC SET CONDITIONS

Test Conditions:

• Engine coolant temperature is less than 36 °C 

(97 

°F) when the engine is started.

• Intake air temperature is less than 36 °C (97 °F) 

when the engine is started.

• Engine coolant temperature is greater than 58 °C 

(136 

°F) When the amount of remaining fuel is 15 

− 40 percent of capacity upon engine start up.

• Engine coolant temperature is greater than 20 °C 

(68 

°F) when the amount of remaining fuel is 40 − 

85 percent of capacity upon engine start up.

• Intake air temperature is greater than 5 °C (41 

°F).

• Fuel temperature is less than 36 °C (97 °F).

• Barometric pressure is greater than 76 kPa (11 

psi).

• Volumetric efficiency is between 20 and 70 per-

cent.

• Fuel tank differential pressure sensor output volt-

age is 1 

− 4 volts.

• When the evaporative emission purge solenoid 

and evaporative emission ventilation solenoid are 
closed, the pressure in the fuel tank rises to 451 
Pa (0.065 psi) or less and the amount of remain-
ing fuel is 15 

− 40 percent of capacity upon 

engine start up.

• When the evaporative emission purge solenoid 

and evaporative emission ventilation solenoid are 
closed, the pressure in the fuel tank rises to 324 
Pa (0.047 psi) or less and the amount of remain-
ing fuel is 40 

− 85 percent of capacity upon 

engine start up.

• Engine speed is greater than 1,600 r/min.

• 10 seconds have elapsed from the start of the 

previous monitoring.

• Monitoring time: 150 seconds.

Judgment Criteria

• The fuel tank internal pressure is greater than 2 

kPa (0.29 psi) after the evaporative emission 
purge solenoid has been driven when the fuel 
tank and vapor line were closed.

.

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function 

− OBD-ll Drive Cycle − 

Procedure 1 

− Evaporative Emission System Leak 

Monitor 

P.13A-4

.

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TROUBLESHOOTING HINTS (The most likely 
causes for this code to be set are:)

• Loose fuel cap.

• Fuel cap relief pressure is incorrect.

• Malfunction of the fuel overflow limiter valve.

• Purge line or vapor line is clogged.

• Malfunction of the fuel tank, purge line or vapor 

line seal.

• Malfunction of the evaporative emission purge 

solenoid.

• Malfunction of the evaporative emission ventila-

tion solenoid.

• Malfunction of the fuel tank differential pressure 

sensor.

• Malfunction of the evaporative emission canister 

seal.

• Evaporative emission canister is clogged.