Mitsubishi Lancer Evolution X. Manual — part 355

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-485

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.

• Engine coolant temperature is more than 60° C

(140° F). <Amount of remaining fuel is 15 − 40

percent of capacity when the engine is started>

• Engine coolant temperature is more than 20° C

(68° F). <Amount of remaining fuel is 40 − 85 per-

cent of capacity when the engine is started>

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

when the engine is started.

• Volumetric efficiency is between 20 and 50 per-

cent.

• Engine speed is more than 1,594 r/min.

AK704743

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

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-486

• 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 451 Pa (0.13 in.Hg). <Amount of
remaining fuel is 15 − 40 percent of capacity when

the engine is started>

• 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 5° C (41° F).
• Fuel temperature is less than 36° C (97° F).
• 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: 150 seconds

Judgment Criterion

• The fuel tank internal pressure is more than −1961

Pa (−

0.58 in.Hg) after the evaporative emission

purge solenoid has been driven when the fuel
tank and vapor line were closed.

.

FAIL-SAFE AND BACKUP FUNCTION

• None

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function − OBD-ll Drive Cycle −

Pattern 4

P.13A-9

.

.

TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CODE TO BE
SET ARE:)

• Loose fuel cap.
• Fuel cap relief pressure is incorrect.
• Fuel overflow limiter valve failed.
• Purge line or vapor line is clogged.
• Fuel tank, purge line or vapor line seal failed.
• Evaporative emission purge solenoid valve failed.
• Evaporative emission ventilation solenoid valve

failed.

• Fuel tank differential pressure sensor failed.
• Evaporative emission canister seal is faulty.
• Evaporative emission canister is clogged.

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-487

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

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 "Special Function"
(7) Select "Evap Leak Monitor"
(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.13A-48

. 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.

AC608435

Data link connector

MB991827

MB991824

MB991910

AB

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

13A-488

STEP 2. Test check valve.
(1) Check valve is a one-way check valve.

(2) Check valve should allow air to flow in only one direction.
Q: Does check valve allow air to pass in one direction

only?
YES : Go to Step 3 .
NO : Replace check valve. Then go to Step 14 .

STEP 3. Check for leaks in evaporative emission hoses A
and B.
Use a hand vacuum pump to test each hose A and B.
Q: Do the hoses hold vacuum?

YES : Go to Step 4 .
NO : Replace any damaged hose. Then go to Step 14 .

STEP 4. Check the evaporative emission purge solenoid
for leaks.
Refer to GROUP 17, Emission Control − Evaporative Emission

Control System − Evaporative Emission Purge Solenoid Check

P.17-76

.

Q: Is the evaporative emission purge solenoid operating

properly?
YES : Go to Step 5 .
NO : Replace the evaporative emission purge solenoid.

Then go to Step 14 .

AK704695

Check valve

AB

AK604287AB

Check valve

AK704688

Hose B

Hose A

AB