Mitsubishi Galant 9G. Manual - part 933
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.8L ENGINE>
13B-32
FAIL-SAFE FUNCTION REFERENCE TABLE
M1131153000631
When the main sensor malfunctions are detected by
the diagnostic test mode, the vehicle is controlled by
means of the following defaults.
MALFUNCTION ITEM
CONTROL CONTENTS DURING MALFUNCTION
Mass airflow sensor
• Uses the throttle position sensor signal and engine speed signal (crankshaft
position sensor signal) for basic injector drive time and basic ignition timing
from the pre-set mapping.
Intake air temperature
sensor
Controls as if the intake air temperature is 25
°C (77°F).
Engine coolant
temperature sensor
Controls as if the engine coolant temperature is 80
°C (176°F). (This control will
be continued until the ignition switch is turned to "LOCK" (OFF) position even
though the sensor signal returns to normal.)
Camshaft position sensor Injects fuel simultaneously into all cylinders. (After the ignition switch is turned to
"ON" position, the No.1 cylinder top dead center is not detected at all.)
Barometric pressure
sensor
Controls as if the barometric pressure is 101 kPa (30 in.Hg).
Knock sensor
Switches the ignition timing from ignition timing for high octane to ignition timing
for standard octane fuel.
Heated oxygen sensor
<front>
Air/fuel ratio closed loop control is not performed.
Heated oxygen sensor
<rear>
Performs the closed loop control of the air/fuel ratio by using only the signal of
the heated oxygen sensor (front) installed on the front side of the catalytic
converter.
Generator FR terminal
No generator output suppression control is performed for the electrical load (to
be operated as an ordinary generator).
Misfire detection
The PCM stops supplying fuel to the cylinder with the highest misfiring rate if a
misfiring that could damage the catalytic converter is detected.
Accelerator pedal position
sensor (main)
• Detects the amount of the accelerator pedal travel through the use of the
accelerator pedal position sensor (sub) signal, but rendering it only as being
approximately one-half the normal opening angle.
• Prohibits the operation of the auto-cruise control.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronically controlled
throttle valve system if the accelerator pedal position sensor (sub) is also
malfunctioning.
Accelerator pedal position
sensor (sub)
• Detects the amount of the accelerator pedal travel through the use of the
accelerator pedal position sensor (main) signal, but rendering it only as being
approximately one-half the normal opening angle.
• Prohibits the operation of the auto-cruise control.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronically controlled
throttle valve system if the accelerator pedal position sensor (main) is also
malfunctioning.