Mitsubishi Montero Sport (2004+). Manual — part 256
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI)
13A-437
STEP 11. Using the oscilloscope, check the injector.
(1) Disconnect the injector intermediate connector A-04 and
connect the test harness special tool (MD998474) in
between.
(2) Connect the oscilloscope probe to each injector
intermediate connector terminal to oscilloscope each
cylinder:
• Terminal No. 3 (green clip of the special tool) when
checking No. 1 cylinder.
• Terminal No. 2 (white clip of the special tool) when
checking No. 2 cylinder.
• Terminal No. 1 (blue clip of the special tool) when check-
ing No. 3 cylinder.
• Terminal No. 7 (yellow clip of the special tool) when
checking No. 4 cylinder.
• Terminal No. 6 (red clip of the special tool) when check-
ing No. 5 cylinder.
• Terminal No. 5 (black clip of the special tool) when
checking No. 6 cylinder.
NOTE: When measuring with the PCM side connector, con-
nect an oscilloscope probe to the each of the following ter-
minals.
.
•
PCM terminal No. 1 when checking No. 1 cylinder injec-
tor
•
PCM terminal No. 9 when checking No. 2 cylinder injec-
tor
•
PCM terminal No. 24 when checking No. 3 cylinder
injector
•
PCM terminal No. 2 when checking No. 4 cylinder injec-
tor
•
PCM terminal No. 10 when checking No. 5 cylinder
injector
•
PCM terminal No. 25 when checking No. 6 cylinder
injector
(3) Start the engine and run at idle.
(4) Measure the waveform.
• The waveform should show a normal pattern similar to
the illustration.
(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the waveform normal?
YES : It can be assumed that this malfunction is intermittent.
Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
NO : Replace the PCM. Then go to Step 12.
AK102982 AB
OSCILLOSCOPE
INJECTOR
INTERMEDIATE
CONNECTOR
MD998474
1 2 3 4
5 6 7 8
AKX01557 AB
A
NORMAL WAVEFORM
A:INJECTOR DRIVE TIME
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI)
13A-438
STEP 12. 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
(2) Check the diagnostic trouble code (DTC).
Q: Are DTC P0201, P0202, P0203, P0204, P0205 and P0206
sets?
YES : Repeat the troubleshooting.
NO : The procedure is complete.
Continue
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI)
13A-439
13A
DTC P0300: Random/Multiple Cylinder Misfire Detected
.
Random Misfire Circuit
• Refer to DTC P0335 − Crankshaft Position Sen-
sor Circuit.
• Refer to DTC P0201 − P0206, Injector Circuit.
.
CIRCUIT OPERATION
• Refer to DTC P0335 − Crankshaft Position Sen-
sor Circuit.
• Refer to DTC P0201 − P0206, Injector Circuit.
.
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
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
.
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI)
13A-440
DTC SET CONDITIONS
Logic Flow Chart
.
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).
• 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 and fuel
shut-off operation.
• The throttle deviation is −0.06 volt/10 ms to +0.06
volt/10 ms.
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
AK204053
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст