Mitsubishi Montero Sport (2004+). Manual — part 302

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-621

TECHNICAL DESCRIPTION

• The PCM monitors the Evaporative Emission

(EVAP) System pressure.

• The PCM controls the evaporative emission ven-

tilation solenoid. It closes the evaporative emis-
sion ventilation solenoid to seal the evaporative
emission canister side of the system.

• The evaporative emission purge solenoid is

opened to allow manifold vacuum to create low
pressure (vacuum) in the EVAP system.

• When the EVAP system develops a vacuum of 2

kPa (0.29 psi), the evaporative emission purge
solenoid is closed and the fuel system vacuum is
maintained at 2 kPa (0.29 psi).

• The PCM determines whether there is a leak in

the EVAP system by monitoring the vacuum
inside the fuel tank.

• The test is stopped when fuel vapor pressure

exceeds predetermined limits.

.

DESCRIPTIONS OF MONITOR METHODS

• Measure reverting pressure after depressurizing

by intake manifold negative pressure and detect
malfunction if reverting pressure rises largely.

.

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-622

LOGIC FLOW CHARTS (Monitor Sequence)

.

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-623

DTC SET CONDITIONS

Test Conditions:

• Fuel level sensor output voltage is 2.4 − 3.7 volts

when the engine is started, and the amount of
remaining fuel is 40

− 85 percent of capacity.

• 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 20 °C

(68

°F).

• Intake air temperature is greater than −10 °C (14

°F).

• Fuel temperature is less than 33 °C (91 °F).

• Barometric pressure is greater than 76 kPa (11

psi).

• 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 rises in the fuel tank is less
than 324 Pa (0.047 psi).

• 10 seconds have elapsed from the start of the

previous monitoring.

• Monitoring time: 10 − 14 minutes.

Judgment Criteria:

• Internal pressure of the fuel tank has changed

greater than 1,177

− 1,373 Pa (0.177 − 0.199 psi)

in 128 seconds after the 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

.

.

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

• Loose fuel cap.

• Fuel cap relief pressure is incorrect.

• Evaporative emission canister seal is leaking.

• Fuel tank, purge line or vapor line seal is leaking.

• Evaporative emission ventilation solenoid dose

not seal.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-624

DIAGNOSIS

Required Special Tool:

• MB991958: Scan tool (MUT-III sub assembly)

• MB991824: V.C.I.

• MB991827: MUT-III USB cable

• MB991911: MUT-III main harness B

STEP 1. Using scan tool MB991958, check evaporative
emission system monitor test.

CAUTION

• To prevent damage to scan tool MB991958, always turn

the ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991958.

• During this test, the PCM automatically increases the

engine speed to 1,600 r/min or greater. Check that the
transmission is set to "P" position.

(1) Connect scan tool MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Erase the DTCs using scan tool MB991958.
(4) Check that the fuel cap is securely closed. (Tighten until

three clicks are heard).

(5) Start the engine.
(6) Select "System Test" and press the "YES" key.
(7) Select "Evap Leak Mon." and press the "YES" key.
(8) During this test, keep the accelerator pedal at the idling

position.
NOTE: If the engine speed does not reach 2,000 r/min dur-
ing the monitor test, adjust the Speed Adjusting Screw
(Refer to

P.13A-883

), and adjust to the standard value.

(9) Keep the engine speed and engine load within the specified

range. When the monitor test starts, the "In Progress" item
on scan tool MB991958 will change from "NO" to "YES".

(10)Turn the ignition switch to the "LOCK" (OFF) position and

disconnect scan tool MB991958.

Q: Is "Evap Leak Mon. Completed. Test Failed and DTCs

Set" displayed on scan tool MB991958?
YES : A malfunction has been detected during the monitor

test. Refer to the Diagnostic Trouble Code Chart

P.13A-26

, and diagnose any other DTCs that are set.

If no other DTC's have been set, go to Step 2 .

NO <"Evap Leak Mon. Completed. Test Passed" is
displayed on scan tool MB991958.> : The evaporative

emission system is working properly at this time.
Explain to the customer that an improperly tightened
fuel cap can cause the MIL to illuminate. Return the
vehicle to the customer.

NO <"Evap Leak Mon. Discontinued. Retest again from
the first" is displayed on scan tool MB991958.> : The

EVAP monitor has been interrupted during the test.
Turn the ignition switch to the "LOCK" (OFF) position
once, and repeat the monitor test.

AK303629AB

MB991911

MB991827

MB991824

16-PIN