Mitsubishi Galant. Manual — part 287

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-373

TECHNICAL DESCRIPTION

•

The manifold differential pressure sensor outputs
a voltage which corresponds to the negative
pressure in the intake manifold.

•

The PCM checks whether the voltage output by
manifold differential pressure sensor is within a
specified range.

DTC SET CONDITIONS

Check Conditions

•

Eight minutes or more have passed after starting
the engine. Note that this is only if the engine
coolant temperature is less than 0

°

C (32

°

F)

when starting.

•

Engine coolant temperature is higher than 45

°

C

(113

°

F).

•

Intake air temperature is higher than 5

°

C (41

°

F).

•

Volumetric efficiency is between 30 and 45
percent.

Judgment Criteria

•

Manifold differential pressure sensor output
voltage has continued to be higher than 4.6 volts
[corresponding to an absolute pressure of 118
kPa (17 psi) or higher] for 2 seconds.

or

•

Manifold differential pressure sensor output
voltage has continued to be lower than 0.1 volt
[corresponding to an absolute pressure of 2.4
kPa (0.3 psi) or lower] for 2 seconds.

Check Conditions

•

Eight minutes or more have passed after starting
the engine. Note that this is only if the engine
coolant temperature is 0

°

C (32

°

F) or more when

starting.

•

Engine coolant temperature is higher than 45

°

C

(113

°

F).

•

Intake air temperature is higher than 5

°

C (41

°

F).

•

Volumetric efficiency is lower than 30 percent.

Judgment Criteria

•

Manifold differential pressure sensor output
voltage has continued to be higher than 4.2 volts
[corresponding to an absolute pressure of 108
kPa (16 psi) or higher] for 2 seconds.

Check Conditions

•

Eight minutes or more have passed after starting
the engine. Note that this is only if the engine
coolant temperature is 0

°

C (32

°

F) or more when

starting.

•

Engine coolant temperature is higher than 45

°

C

(113

°

F).

•

Intake air temperature is higher than 5

°

C (41

°

F).

•

Volumetric efficiency is higher than 70 percent.

Judgment Criteria

•

Manifold differential pressure sensor output
voltage has continued to be lower than 1.8 volts
[corresponding to an absolute pressure of 46 kPa
(4.6 psi) or lower] for 2 seconds.

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

•

Manifold differential pressure sensor failed.

•

Open or shorted manifold differential pressure
sensor circuit, or loose connector.

•

PCM failed.

DIAGNOSIS

Required Special Tools
MB991502: Scan Tool (MUT-II)

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-374

STEP 1. Using scan tool MB991502, check data list item 95:
Manifold Differential Pressure Sensor.

CAUTION

To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK"(OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991502 to the data reading mode for item

95, Manifold Differential Pressure Sensor.

•

While engine is idling, pressure should be between 62
and 76 kPa.

(4) 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(

P.00-8

).

NO : Go to Step 2.

STEP 2. Check connector B-18 at manifold differential
pressure sensor for damage.
Q: Is the connector in good condition?

YES : Go to Step 3.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection(

P.00E-2

). Then go to Step 12.

STEP 3. Check the sensor supply voltage at manifold
differential pressure sensor harness side connector B-18.
(1) Disconnect the connector B-18 and measure at the harness

side.

(2) Turn the ignition switch to "ON" position.
(3) Measure the voltage between terminal 3 and ground.

•

Voltage should be between 4.8 and 5.2 volts.

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

Q: Is the voltage normal?

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

AC003081 AB

16 PIN

MB991502

ACX02483

CONNECTOR:B-18

MANIFOLD
DIFFERETIAL
PRESSURE
SENSOR

AE

AKX01427

B-18 HARNESS SIDE
CONNECTOR

1

2

3

AE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-375

STEP 4. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 5.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection(

P.00E-2

). Then go to Step 12.

STEP 5. Check for open circuit and short circuit to ground
between manifold differential pressure sensor connector
B-18 terminal 3 and PCM connector C-40 terminal 46.
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 12.
NO : Repair it. Then go to Step 12.

STEP 6. Check the continuity at manifold differential
pressure sensor harness side connector B-18.
(1) Disconnect the connector B-18 and measure at the harness

side.

(2) Measure the continuity between terminal 2 and ground.

•

Should be less than 2 ohm.

Q: Is the continuity normal?

YES : Go to Step 9.
NO : Go to Step 7.

AK000280

CONNECTOR : C-40

PCM

AV

ACX02483

CONNECTOR:B-18

MANIFOLD
DIFFERETIAL
PRESSURE
SENSOR

AE

AK000280

CONNECTOR : C-40

PCM

AV

AKX01426

B-18 HARNESS SIDE
CONNECTOR

1

2

3

AE

MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI) <3.0L>

13B-376

STEP 7. Check connector C-40 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 8.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection(

P.00E-2

). Then go to Step 12.

STEP 8. Check for open circuit and harness damage
between manifold differential pressure sensor connector
B-18 terminal 2 and PCM connector C-40 terminal 57.
Q: Is the harness wire in good condition?

YES : Replace the PCM. Then go to Step 12.
NO : Repair it. Then go to Step 12.

STEP 9. Check connector C-41 at PCM for damage.
Q: Is the connector in good condition?

YES : Go to Step 10.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection(

P.00E-2

). Then go to Step 12.

AK000280

CONNECTOR : C-40

PCM

AV

ACX02483

CONNECTOR:B-18

MANIFOLD
DIFFERETIAL
PRESSURE
SENSOR

AE

AK000280

CONNECTOR : C-40

PCM

AV

AK000280

CONNECTOR : C-41

PCM

AY