Mitsubishi Montero (2004+). Manual - part 253

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-499

STEP 19. Check for open circuit or short circuit to ground
or harness damage between camshaft position sensor
connector B-10 (terminal No. 1) and PCM connector D-134
(terminal No.88).

NOTE: Check harness after checking intermediate connector
B-08. If intermediate connector B-08 is damaged, repair or
replace it. Refer to GROUP 00E, Harness Connector Inspec-
tion

P.00E-2

. Then go to Step 21.

Q: Is the harness wire in good condition?

YES : Go to Step 20.
NO : Repair it. Then go to Step 21.

STEP 20. Check the camshaft position sensing cylinder.
Q: Is the camshaft position sensing cylinder in good

condition?
YES : Replace the camshaft position sensor. Then go to

Step 21.

NO : Repair it. Then go to Step 21.

AK200965

B-10(B)

CONNECTOR: B-10

HARNESS
CONNECTOR:
COMPONENT SIDE

AK201166

CONNECTOR: D-134

PCM

D-134(GR)

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-500

STEP 21. Test the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to

Diagnostic Function

− OBD-II Drive Cycle − Procedure 6 −

Other Monitor

P.13A-4

(2) Check the diagnostic trouble code (DTC).
Q: Is DTC P0340 set?

YES : Retry the troubleshooting.
NO : The inspection is complete.

DTC P0401: Exhaust Gas Recirculation Flow Insufficient Detected

TECHNICAL DESCRIPTION

• When the EGR valve (stepper motor) is actuated

from the fully closed position toward the open
position while the engine is running, EGR gas
flows.

• The PCM checks how the EGR gas flow signal

changes.

DESCRIPTIONS OF MONITOR METHODS
Small manifold pressure change during exhaust gas

recirculation (EGR) operation from closed to
open.

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)

• EGR stepper motor monitor

Sensor (The sensor below is determined to be

normal)

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

• Accelerator pedal position sensor

• Manifold absolute pressure sensor

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-501

DTC SET CONDITIONS

Logic Flow Chart

Check Conditions

• At least 20 seconds have passed since the last

monitor was complete.

• Engine coolant temperature is higher than 76°C

(169

°F).

• Engine speed is at between 910 and 1,650 r/min.

• Intake air temperature is higher than −10°C

(14

°F).

• Barometric pressure is higher than 76 kPa (22.4

in.Hg).

• Vehicle speed is 30 km/h (19 mph) or more.

• At least 90 seconds have passed since manifold

absolute pressure sensor output voltage fluctu-
ated 1.5 volts or more.

• Battery positive voltage is higher than 10.3 volts.

• The accelerator pedal is not closed.

• Volumetric efficiency is lower than 28 percent.

START

END

YES

MALFUNCTION

GOOD

MONITORING

CONDITIONS

MEASURE MANIFOLD

PRESSURE (P1)

MEASURE MANIFOLD

PRESSURE (P2)

EGR VALVE OPEN

P2 - P1 < P0 *

SPECIFIED TIMES

AK302950

P0 : THRESHOLD VALUE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-502

• The PCM monitors for this condition for 3 cycles

of 2 seconds each during the drive cycle.

Judgement Criteria

• When the EGR valve opens to the prescribed

opening, intake manifold pressure fluctuation
width is lower than 2.5 kPa (0.74 in.Hg).

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 5

− Exhaust Gas Recirculation (EGR)

System Monitor

P.13A-4

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

• Dirtiness of the EGR valve and EGR passage.

• EGR valve (stopper motor) failed.

• Open or shorted EGR valve (stopper motor) cir-

cuit, or loose connector.

• Manifold absolute pressure sensor failed.

• PCM failed.

DIAGNOSIS

Required Special Tools:

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

• MB991824: V.C.I.

• MB991827: USB Cable

• MB991911: Main Harness B

STEP 1. Check the EGR system
Refer to GROUP 17, Emission Control System

− Exhaust Gas

Recirculation (EGR) System

− General Information

P.17-68

Q: Are there any abnormalities?

YES : Go to Step 2.
NO : Repair it. Then go to Step 3.

STEP 2. Using scan tool MB991958, check data list item 95:
Manifold 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 MB991958.
(1) Connect scan tool MB991958 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991958 to the data reading mode for item

95, Manifold Differential Pressure Sensor.

(4) Warm up the engine to normal operating temperature: 80

°C

to 95

°C (176°F to 203°F).

• Should be between 20.6 − 34.0 kPa (6.1 − 10.0 in.Hg) at

engine idling.

(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?

YES : Clean the EGR valve and EGR passage. Then go to

Step 3.

NO : Refer to DTC P0106

− Manifold Absolute Pressure

Sensor Circuit Range/Performance Problem

P.13A-51

, DTC P0107

− Manifold Absolute Pressure

Sensor Circuit Low Input

P.13A-68

, DTC P0108

−

Manifold Absolute Pressure Sensor High Input

P.13A-84

AK302970

MB991911

MB991824

MB991827

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