Mitsubishi Galant 9G. Manual — part 658

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-74

DTC SET CONDITIONS <Range/Performance problem

− high input>

Logic Flow Chart

Check Conditions

• 8 minutes or more have passed since the engine

starting sequence was completed, when the
engine coolant temperature at engine start is 0

°C

(32

°F) or lower.

• Engine speed is 1,500 r/min or lower.

• Throttle position sensor output voltage is 0.8 volt

or lower.

Judgement Criteria

• Manifold absolute pressure is 89 kPa (26.3 in.Hg)

or higher for 2 seconds.

.

START

YES

YES

YES

NO

NO

NO

PRESSURE > 89kPa (26.3in.Hg)

CONTINUOUS

FAILURE FOR 2secs

MALFUNCTION

END

GOOD

MONITORING

CONDITIONS

AK401473

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-75

DTC SET CONDITIONS <Range/Performance problem

− low input>

Logic Flow Chart

Check Conditions

• 8 minutes or more have passed since the engine

starting sequence was completed, when the
engine coolant temperature at engine start is 0

°C

(32

°F) or lower.

• Engine speed is 1,500 r/min or higher.

• Throttle position sensor output voltage is 3.5 volts

or higher.

Judgement Criteria

• Manifold absolute pressure is 45 kPa (13.3 in.Hg)

or lower for 2 seconds.

.

OBD-II DRIVE CYCLE PATTERN

Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 6

− Other Monitor

P.13A-6

.

.

TROUBLESHOOTING HINTS (The most
likely causes for this code to be set are:)

• Manifold absolute pressure sensor failed.

• Harness damage.

• Connector damage.

• PCM failed.

START

YES

YES

YES

NO

NO

NO

PRESSURE <

45kPa (13.3in.Hg)

CONTINUOUS

FAILURE FOR 2secs

MALFUNCTION

END

GOOD

MONITORING

CONDITIONS

AK401474

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-76

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991910: Main Harness A

• MB991923: Power Plant ECU Check Harness

STEP 1. Using scan tool MB991958, check data list item 95:
Manifold Absolute 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) Turn the ignition switch to the "ON" position.
(3) Set scan tool MB991958 to the data reading mode for item

95, Manifold Absolute Pressure Sensor.

• When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg).

• When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg).

• When altitude is 1,200 m (3,937 feet), 88 kPa (26.0

in.Hg).

• When altitude is 1,800 m (5,906 feet), 81 kPa (23.9

in.Hg).

(4) Start the engine.

• When the engine is idling, 19 − 33 kPa (5.6 − 9.7 in.Hg).

• When the engine is suddenly revved, manifold absolute

pressure varies.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
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.00-14

.

NO : Go to Step 2.

AK303804AB

MB991910

DATA LINK
CONNECTOR

MB991824

MB991827

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>

13A-77

STEP 2. Measure the sensor output voltage at manifold
absolute pressure sensor connector B-02 by backprobing.
(1) Do not disconnect the connector B-02.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 1 and ground by

backprobing.

• When altitude is 0 m (0 foot), voltage should be 3.7 and

4.3 volts.

• When altitude is 600 m (1,969 feet), voltage should be

3.4 and 4.0 volts.

• When altitude is 1,200 m (3,937 feet), voltage should be

3.2 and 3.8 volts.

• When altitude is 1,800 m (5,906 feet), voltage should be

2.9 and 3.5 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is measured the voltage normal?

YES : Go to Step 10.
NO : Go to Step 3.

STEP 3. Measure the sensor supply voltage at manifold
absolute pressure sensor connector B-02 by backprobing.
(1) Do not disconnect the connector B-02.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal No. 3 and ground by

backprobing.

• Voltage should be between 4.9 and 5.1 volts.

(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage between 4.9 and 5.1 volts?

YES : Go to Step 6.
NO : Go to Step 4.

AK303809

1

2

3

AB

CONNECTOR: B-02

B-02 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

3

2

1

AK203034

B-02 HARNESS
CONNECTOR:
HARNESS SIDE

AG

AK303809

1

2

3

AB

CONNECTOR: B-02

B-02 (B)

HARNESS CONNECTOR:
COMPONENT SIDE

3

2

1

AK203036

B-02 HARNESS
CONNECTOR:
HARNESS SIDE

AG