Mitsubishi Montero (2004+). Manual — part 242

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-455

STEP 11. Check the following items.
(1) Check the following items, and repair or replace the

defective component.

a. Check for skipped timing belt teeth.
b. Check compression.

c. EGR valve failed.

Q: Are there any abnormalities?

YES : Go to Step 12.
NO : Repair or replace it. Then go to Step 13.

STEP 12. Replace the injector.
(1) Replace the injector.
(2) 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

.

(3) Check the diagnostic trouble code (DTC).
Q: Is DTC P0300 set?

YES : Replace the PCM. Then go to Step 13.
NO : The inspection is complete.

STEP 13. 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 P0300 set?

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

DTC P0301: Cylinder 1 Misfire Detected, DTC P0302: Cylinder 2 Misfire Detected, DTC P0303: Cylinder
3 Misfire Detected, DTC P0304: Cylinder 4 Misfire Detected, DTC P0305: Cylinder 5 Misfire Detected,
DTC P0306: Cylinder 6 Misfire Detected

.

Misfire Detected Circuit

• Refer to DTC P0201 − P0206, Injector Circuit.

P.13A-421

.

CIRCUIT OPERATION

• Refer to DTC P0201 − P0206, Injector Circuit.

P.13A-421

.

TECHNICAL DESCRIPTION

• If a misfire occurs while the engine is running, the

engine speed changes for an instant.

• The PCM checks for such changes in engine

speed.

.

DESCRIPTIONS OF MONITOR METHODS
Monitor angular acceleration of crankshaft and

detect malfunction when negative variation of the
angular acceleration is large.

.

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)

• Not applicable

AK200960

1

2

B-03(GR)

B-11(GR)

B-35(GR)

B-33(GR)

B-02(GR)

B-01(GR)

CONNECTORS: B-01, B-02, B-03, B-11,

B-33, B-35

AB

HARNESS CONNECTOR:
COMPONENT SIDE

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-456

Sensor (The sensor below is determined to be

normal)

• Camshaft position sensor

• Volume airflow sensor

• Engine coolant temperature sensor

• Intake air temperature sensor

• Barometric pressure sensor

• Throttle position sensor

.

DTC SET CONDITIONS

Logic Flow Chart

.

START

MONITORING

CONDITIONS

CALCULATE CRANKSHAFT

ANGULAR ACCELERATION (An)

An < TH

MF

(Ne, v)

MISFIRE

CALCULATE PERCENT MISFIRE (R

MF

)

END

NO

NO

NO

NO

NO

NO

YES

YES

YES

YES

YES

YES

GOOD

WITHIN 1000rev

R

MF

> SPECIFIED VALUE

MALFUNCTION

(EXCEED STD ×1.5)

GOOD

MALFUNCTION

(DAMAGE THE CAT.)

GOOD

R

MF

> TH

CD

(Ne, v)

CALCULATE PERCENT MISFIRE (R

MF

)

WITHIN 200rev

Ne: ENGINE SPEED
v: VOLUMETRIC EFFICIENCY

AK302943

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-457

Check Conditions

• Engine speed is between 440 and 6,000 r/min.

• Engine coolant temperature is higher than −10°C

(14

°F).

• Barometric pressure is higher than 76 kPa (22.4

in.Hg).

• Volumetric efficiency is at between 30 and 60

percent.

• Adaptive learning is complete for the vane which

generates a crankshaft position signal.

• While the engine is running, excluding gear shift-

ing, deceleration, sudden acceleration/decelera-
tion and A/C compressor switching.

• The throttle deviation is −0.06 V/10 ms to +0.06

V/10 ms.

Judgement Criteria (change in the angular accel-

eration of the crankshaft is used for misfire
detection).

• Misfire has occurred more frequently than

allowed during the last 200 revolutions [when the
catalyst temperature is higher than 950

°C

(1,742

°F)].

or

• Misfire has occurred in 20 or more of the last

1,000 revolutions (corresponding to 1.5 times the
limit of emission standard).

.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function

− OBD-II Drive Cycle −

Procedure 6

− Other Monitor

P.13A-4

.

.

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

• Ignition system related part(s) failed.

• Low compression pressure.

• Injector failed.

• PCM failed.

DIAGNOSIS

STEP 1. Check the spark plugs.

CAUTION

Do not attempt to adjust the gap of the iridium plug. Clean-
ing of the iridium plug may result in damage to the iridium
and platinum tips. Therefore, if carbon deposits must be
removed, use a plug cleaner and complete cleaning within
20 seconds to protect the electrode. Do not use a wire
brush.
(1) For the right bank cylinder, remove the intake manifold.
(2) Check the plug gap and replace if the limit is exceeded.

Standard value: 1.0

− 1.1 mm (0.039 − 0.043 inch)

Limit: 1.3 mm (0.051 inch)

Q: Is the plug gap at the standard value?

YES : Go to Step 2.
NO : Replace the spark plug. Then go to Step 9.

AKX01327AB

IRIDIUM
TIP

PLATINUM
TIP

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-458

STEP 2. Check the spark plug cable.
(1) Check the cap and coating for cracks.
(2) Measure the resistance.

Limit: maximum 9 k

Ω

Q: Is the resistance normal?

YES : Go to Step 3.
NO : Replace the spark plug cable. Then go to Step 9.

STEP 3. Check the injector.
(1) Disconnect the injector connector B-01, B-33, B-02, B-35,

B-03, B-11.

(2) Measure the resistance between injector side connector

terminal No. 1 and No. 2.

Standard value: 13

− 16 ohms [at 20°C (68°F)]

Q: Is the resistance between 13 and 16 ohms [at 20

°C

(68

°F)]?

YES : Go to Step 4.
NO : Replace the injector. Then go to Step 9.

AKX00382

AK200960

1

2

B-03(GR)

B-11(GR)

B-35(GR)

B-33(GR)

B-02(GR)

B-01(GR)

CONNECTORS: B-01, B-02, B-03, B-11,

B-33, B-35

AB

HARNESS CONNECTOR:
COMPONENT SIDE

AKX01414AB

INJECTOR SIDE
CONNECTOR

1 2