Mitsubishi Outlander GS45X. Manual - part 903

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-545

TECHNICAL DESCRIPTION

• The ECM monitors the Evaporative Emission 

(EVAP) System pressure.

• The ECM 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 ECM 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)

• Mass airflow sensor

• Barometric pressure sensor

• Intake air temperature sensor

• Engine coolant temperature sensor

.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-546

DTC SET CONDITIONS

Logic Flow Chart (Monitor Sequence)

.

Check 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 more than 20°C 

(68

°F).

• When the evaporative emission purge solenoid 

and evaporative emission ventilation solenoid are 
closed, the change of the pressure in the fuel 
tank is less than 324 Pa (0.09 in.Hg).

• Amount of remaining fuel is 40 − 85 percent of 

capacity when the engine is started.

• Barometric pressure is more than 76 kPa (22.4 

in.Hg).

• Intake air temperature is more than −10°C (14°F).

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

AK604523

Start

Yes

No

Monitoring 
conditions?

Depressurize fuel tank pressure

Yes

Yes

No

No

Gross leak 

monitoring conditions

Shut purge line

Specified times

have passed

Malfunction

(Gross leak)

Measure reverting
pressure:     PFT  

Yes

Yes

No

No

PFT > PT

Specified times

monitored

Malfunction

End

Good

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-547

• Fuel tank differential pressure sensor output volt-

age is between 1.0 and 4.0 volts.

• At least 10 seconds have passed since the last 

monitor was complete.

• Monitoring time: 10 − 14 minutes

Judgement Criterion

• In case the amount of change in the pressure that 

is monitored for a given length of time inside the 
tank is beyond the specified value after sealing 
off the fuel tank and the vapor line.
NOTE: The specified value varies depending on 
the fuel temperature and fuel level.

.

OBD-ll DRIVE CYCLE PATTERN

Refer to Diagnostic Function 

− OBD-II Drive Cycle − 

Pattern 6 

P.13B-11

.

.

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 evaporative emission canister 

seal.

• Malfunction of the fuel tank, purge line or vapor 

line seal.

• Malfunction of the evaporative emission ventila-

tion solenoid.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>

13B-548

STEP 1. Using scan tool MB991958, check the 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 ECM will automatically increase 

the engine speed to 1,600 r/min or greater. Check that 
the transaxle 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."
(7) Select "Evap Leak Mon."
(8) During this test, keep the accelerator pedal at the idle 

position.

(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 and 
diagnose any other DTCs that are set 

P.13B-50

. 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 monitoring from Step 1 .

AK700568AB

MB991824

MB991827

MB991910

Data link
connector