Mitsubishi Lancer Evolution X. Manual - part 354

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-481

STEP 5. Using scan tool MB991958, check data list item 52: 
Fuel Tank Differential Pressure Sensor.

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) Disconnect hose E from the evaporative emission canister, 

and plug the hose.

(3) Turn the ignition switch to the "ON" position.
(4) Remove the fuel cap.
(5) Set scan tool MB991958 to the data reading mode for item 

52, Fuel Tank Differential Pressure Sensor.

• Output voltage should be between 1,500 to 3,500 mV.

(6) Connect the evaporative emission system pressure pump 

(Miller number 6872A) to the fuel tank filler tube by using 
fuel tank adapter (MLR-8382) and pressurize the fuel tank.

• The fuel tank pressure reading should increase.

(7) Turn the ignition switch to the "LOCK" (OFF) position. Then 

disconnect scan tool MB991958.

(8) Remove the evaporative emission system pressure pump 

(Miller number 6872A) and the fuel tank adapter 
(MLR-8382), and reinstall the fuel cap.

(9) Connect hose E to the evaporative emission canister.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

AK704692 AB

Plug

Hose E

AK704700

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-482

Q: Is the sensor operating properly?

YES : It can be assumed that this malfunction is intermittent. 

Refer to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points − How to 

Cope with Intermittent Malfunctions 

P.00-15

.

NO :  Replace the ECM. When the ECM is replaced, 

register the ID code. Refer to GROUP 42B, Diagnosis 
− ID Code Registration Judgment Table <Vehicles with 

KOS> 

P.42B-11

 or GROUP 42C, Diagnosis − ID 

Codes Registration Judgment Table <Vehicles with 
WCM> 

P.42C-9

. Then go to Step 7 .

STEP 6. Check harness connector D-21 at the fuel tank 
differential pressure sensor and harness connector B-10 
at ECM for damage.
Q: Is the harness connector in good condition?

YES : Replace the fuel tank differential pressure sensor. 

Then go to Step 7 .

NO :  Repair or replace it. Refer to GROUP 00E, Harness 

Connector Inspection 

P.00E-2

. Then go to Step 7 .

STEP 7. 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 − Pattern 23 

P.13A-9

.

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0453 set?

YES : Retry the troubleshooting.
NO :  The inspection is complete.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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13A

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

.

AK704684

L

A

B

C

D

E

F

H

G

I

J

K

AB

Intake manifold

Fuel tank

Check valve

Evaporative emission
purge solenoid

Evaporative emission
ventilation solenoid

Evaporative emission
canister

Fuel tank differential 
pressure sensor

System diagram

Air filter

Vent pipe

AK704685

Evaporative emission canister

AB

AK704686

Evaporative emission
ventilation solenoid

AB

AK704687

AB

Evaporative emission purge solenoid

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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TECHNICAL DESCRIPTION

• The fuel tank may be under a slight pressure or 

vacuum depending on the state of the Evapora-
tive Emission (EVAP) System. The ECM monitors 
and responds to these pressure/vacuum 
changes. If the pressure/vacuum varies from the 
specified range, the ECM will set DTC P0455.

• The ECM energizes the evaporative emission 

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

• The evaporative emission purge solenoid is acti-

vated to apply engine manifold vacuum to the 
EVAP 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 ECM determines whether there is a leak or 

clog in the fuel system by measuring the change 
in vacuum 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

Continuous

.

MONITOR EXECUTION CONDITIONS 
(OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored 

in memory for the item monitored below)

• Not applicable

 Sensor (The sensors below are determined to be 

normal)

• Not applicable

.