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Mitsubishi Eclipse. Manual - part 246

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-477

LOGIC FLOW CHARTS (Monitor Sequence)

DTC SET CONDITIONS
Remaining fuel amount is 15

− 40 percent (fuel level

sensor output voltage is 1.4

− 2.4 volts)

Test Conditions A: At Start up

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

when the engine is started.

• The engine coolant temperature 36°C (97°F) or

less when the engine is started.

Test Conditions B: For Test to Run

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

with in 800 seconds have elapsed since the
engine was started.

• Engine coolant temperature is higher than 60°C

(140

°F).

• Power steering pressure switch: "OFF"

• Barometric pressure is above 76 kPa (11 psi).

START

END

MONITORING
CONDITIONS?

GROSS LEAK

MONITORING CONDITIONS

SPECIFIED TIMES

MONITORED

SPECIFIED TIMES

HAVE PASSED

YES

DEPRESSURIZE FUEL TANK PRESSURE

YES

SHUT PURGE LINE

MALFUNCTION

(GROSS LEAK)

GOOD

YES

AC210304

0.04in, 0.02in GROSS LEAK MONITOR

MEASURE REVERTING
PRESSURE :

PFT

PFT > PT

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-478

• Fuel tank differential pressure sensor output

mb991958voltage is 1 to 4 volts.

• Vehicle speed is 20 km/h (12.4 mph) or more.

Test Conditions C: For Test to Stop

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

• When the evaporative emission purge solenoid

and evaporative emission ventilation solenoid are
closed, the pressure rises higher 451 Pa (0.065
psi).

• The pressure fluctuation width is higher than 647

Pa (0.094 psi).

• 10 seconds have elapsed from the start of the

previous monitoring.

Judgment Criteria

• Internal pressure of the fuel tank has changed

more than 785 Pa (0.114 psi) in 20 seconds after
the tank and vapor line were closed.

• ECM monitors for this condition once during drive

cycle.

NOTE: The monitoring time depends on the fuel
level and the temperature in the fuel tank (75

−

125

seconds).

DTC SET CONDITIONS
Remaining fuel amount is 40

− 85 percent (fuel level

sensor output voltage is 2.4

− 3.7 volts)

Test Conditions A: At Start up

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

when the engine is started.

• The engine coolant temperature 36°C (97°F) or

less when the engine is started.

Test Conditions B: For Test to Run

• The fuel tank temperature is 36°C (97°F) or less.

• Barometric pressure is above 76 kPa (11 psi).

• Fuel tank differential pressure sensor output volt-

age is 1 to 4 volts.

Test Conditions C: For Test to Stop

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

• Engine coolant temperature is less than 20°C

(68

°F).

• When the evaporative emission purge solenoid

and evaporative emission ventilation solenoid are
closed, the pressure rises higher 324 Pa (0.047
psi).

• 10 seconds have elapsed from the start of the

previous monitoring.

Judgment Criteria

• Internal pressure of the fuel tank has changed

more than 1.9 kPa (0.28 psi) in 128 seconds after
the tank and vapor line were closed.

• ECM monitors for this condition once during drive

cycle.

NOTE: The monitoring time depends on the fuel
level and the temperature in the fuel tank (10

−

minutes).

OBD-ll DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-ll Drive Cycle −

Procedure 1

− Evaporative Emission System Leak

Monitor

P.13A-5

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 faulty.

• Fuel tank, purge line or vapor line seal failed.

• Evaporative emission ventilation solenoid failed.

OVERVIEW OF TROUBLESHOOTING

• To determine the cause of DTC P0442, a perfor-

mance test is needed. The performance test uses
a mechanical vacuum gauge and scan tool
MB991958 set on the fuel tank differential pres-
sure sensor (TANK PRES SNER 73.) The
mechanical gauge reading is used to verify scan
tool MB991958 reading. A comparison of the
mechanical gauge to scan tool MB991958 deter-
mines the problem in the system.

• Prior to doing the performance test, several sim-

ple inspections are needed to exclude some pos-
sibilities of the symptom.

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

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-479

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.

• With this monitor, the ECM <M/T> or PCM <A/T> auto-

matically increases the engine speed to 1,600 r/min or
more. Check that the transaxle is set to "neutral" <M/T>
or "P" <A/T> 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 the 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 the monitor, 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, adjustment of the Speed Adjusting
Screw may be needed. Refer to

P.13A-928

. 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: What is displayed on the scan tool MB991958?

"Evap Leak Mon. Completed Test Passed" : The

evaporative emission system is working properly at
this time. Explain to customer that improperly
tightened fuel cap can cause MIL to turn on, and
return the vehicle.

"Evap Leak Mon. Completed. Test Failed and DTCs Set"
:

A malfunction has been detected during the monitor
test. Go to Step 2.

"Evap Lead Mon. discontinued. Retest again from the
first" : The monitor was discontinued for a certain reason

(vehicle speed input from computer, engine speed
and engine load deviating from specified range). Turn
the ignition switch to the "LOCK" (OFF) position once,
and repeat the monitoring from the Step 1.

AC303127

MB991911

16-PIN

MB991827

MB991824

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI) <2.4L>

13A-480

STEP 2. Check evaporative emission purge solenoid for
leaks.
(1) Remove the battery.
(2) Remove the air intake hose. (Refer to GROUP 15, Air

Cleaner

P.15-6

(3) Disconnect hose B from the evaporative emission purge

solenoid side, and connect a hand vacuum pump to the
nipple of the evaporative emission purge solenoid.

(4) Apply a pressure on the hand vacuum pump, and confirm

that air is maintained.

(5) Disconnect the hand vacuum pump, and connect hose B to

the evaporative emission purge solenoid.

Q: Is the evaporative emission purge solenoid in good

condition?
YES : Go to Step 3.
NO : Replace the evaporative emission purge solenoid.

Then go to Step 18.

STEP 3. Check for leaks in the evaporator line hose A to
hose C.

The leakage test with a hand vacuum pump on each hose
from hose A to hose C.

Q: Are the hoses in good condition?

YES : Go to Step 4.
NO : Replace the inferior hose. Then go to Step 18.

STEP 4. Check for leaks in the chamber.
(1) Connect a hand vacuum pump to the nipple.
(2) Plug the other nipple.
(3) Apply vacuum with the hand vacuum pump, and confirm

that the applied vacuum does not fluctuate.

Q: Is the chamber in good condition?

YES : Go to Step 5.
NO : Replace the chamber. Then go to Step 18.

AC000223

HOSE B

THROTTLE
BODY

AC000182

EVAPORATIVE EMISSION
PURGE SOLENOID

AC000223

THROTTLE
BODY

HOSE B

HOSE A

HOSE C

AC000223

THROTTLE
BODY

CHAMBER

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