Mitsubishi Montero Sport (2004+). Manual — part 293

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-585

.

CIRCUIT OPERATION

• The PCM (terminal 46) supplies a 5-volt refer-

ence signal to the fuel tank differential pressure
sensor (terminal 3). The fuel tank differential
pressure sensor (terminal 2) is grounded through
the PCM (terminal 57).

• The fuel tank differential pressure sensor (termi-

nal 1) returns a voltage signal to the PCM (termi-
nal 92) that is proportional to the pressure in the
fuel tank.

.

TECHNICAL DESCRIPTION

• The PCM monitors the fuel tank differential pres-

sure sensor output voltage.

• The PCM determines whether the fuel tank differ-

ential pressure sensor signal voltage is within
normal operating parameters.

NOTE: In rare cases, this DTC may be also set
under some fuel and driving conditions regardless of
the fuel pressure sensor output voltage when the fuel
system is clogged.

.

DESCRIPTIONS OF MONITOR METHODS

• Compare purge solenoid status with fuel tank dif-

ferential pressure sensor output voltage.

.

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)

• Evaporative emission purge solenoid monitor

• Evaporative emission ventilation solenoid monitor

Sensor (The sensors below are determined to be

normal)

• Volume airflow sensor

• Barometric pressure sensor

• Intake air temperature sensor

• Engine coolant temperature sensor

.

PCM

C-90 (GR) C-91 (GR)

AC203152 AB

CONNECTORS: C-90, C-91

AC002614

CONNECTOR: E-28

FUEL TANK DIFFERENTIAL
PRESSURE SENSOR

AE

E-28 (B)

AC203242

CONNECTOR: E-44

AB

E-44

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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LOGIC FLOW CHARTS (Monitor Sequence)

.

DTC SET CONDITIONS

Test Conditions: For Test to Run

• Intake air temperature is between 5 °C (41 °F)

and 45

°C (113 °F) or greater.

• Engine speed is greater than 1,600 r/min.

• Volumetric efficiency is between 25 and 80 per-

cent.

Judgment Criteria

• When the evaporative emission purge solenoid is

fully operational (100 percent ratio), the fuel dif-
ferential pressure sensor output voltage remains
4.0 volts or greater for ten seconds.

.

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:)

• Malfunction of the fuel tank differential pressure

sensor.

• A damaged harness in the fuel tank differential

pressure sensor circuit.

• Malfunction of the PCM.

.

NO

YES

CONTINUOUS

FAILURE FOR 10 SECS

START

END

NO

NO

NO

YES

YES

YES

MALFUNCTION

GOOD

MONITORING

CONDITIONS

OUTPUT VOLTAGE

< 1.0V

OUTPUT VOLTAGE

> 4.0V

AC306648

RANGE CHECK - MIN/MAX

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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OVERVIEW OF TROUBLESHOOTING

• DTC P0453 can be set by a faulty fuel tank differ-

ential pressure sensor or related circuit, or PCM
failure.

• To check a system blockage, do a performance

test which uses a mechanical vacuum gauge and
scan tool MB991958 set on the fuel tank differen-
tial pressure sensor (TANK PRS SNSR 73).

The mechanical gauge reading is used to verify
scan tool MB991958 reading.
A comparison of the mechanical gauge with the
reading on scan tool MB991958 will locate a
problem in the system.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: MUT-III USB cable

• MB991911: MUT-III main harness B

• MB991658: Test harness set

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

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MULTIPORT FUEL INJECTION (MFI)

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STEP 1. Using scan tool MB991958, check data list item 73:
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 MB991502.
(1) Connect scan tool MB991958 to the data link connector.

(2) Disconnect hose E from the evaporative emission canister

side, 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.

• Item 73, Fuel Tank Differential Pressure Sensor.

• The fuel tank pressures reading on the scan tool

should be

−3.3 to 3.3 kPa (−0.97 to 0.97 inHg).

(6) Connect an evaporative emission system pressure pump to

the fuel filler neck 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) Disconnect the evaporative emission system pressure

pump, and reinstall the fuel cap.

(9) Connect hose E to the canister.
Q: Is the fuel tank pressure between

−3.3 and 3.3 kPa

(

−0.97 and 0.97 inHg)?

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 Malfunction

P.00-7

). Then go

to Step 16 .

NO : Go to Step 2 .

AK303629AB

MB991911

MB991827

MB991824

16-PIN

AC005140

HOSE E

AC

ACX01358