Mitsubishi Grandis. Manual - part 692
TROUBLESHOOTING
MULTIPORT FUEL INJECTION (MPI)
13A-19
Malfunctioning item
Control contents during malfunction
Air flow 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.
Barometric pressure
sensor
Controls as if the barometric pressure is 101 kPa.
Throttle position sensor
(main)
• Controls the throttle valve position through the use of the throttle position sensor
(sub) signal.
• Renders the amount of accelerator pedal travel as being approximately one-half
the normal opening angle.
• Prohibits the operation of the engine speed feedback control.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronic-controlled throttle
valve system if the throttle position sensor (sub) is also malfunctioning.
Throttle position sensor
(sub)
• Controls the throttle valve position through the use of the throttle position sensor
(main) signal.
• Renders the amount of accelerator pedal travel as being approximately one-half
the normal opening angle.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronic-controlled throttle
valve system if the throttle position sensor (main) is also malfunctioning.
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.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronic-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.
• Cuts off fuel when the engine speed exceeds 3,000 r/min.
• Suppresses the engine output by stopping the electronic-controlled throttle
valve system if the accelerator pedal position sensor (main) is also
malfunctioning.
Engine coolant
temperature sensor
Controls as if the engine coolant temperature is 80
°C. (This control will be
continued until the ignition switch is turned to the "LOCK" (OFF) position even
though the sensor signal returns to normal.)
Camshaft position
sensor
Injects fuel into the cylinders in the order 1-3-4-2 with irregular timing. (After the
ignition switch is turned to the "ON" position, the No. 1 cylinder top dead center is
not detected at all.)
Oxygen sensor <front> Air/fuel ratio closed loop control is not performed.
Oxygen sensor <rear> Performs the closed loop control of the air/fuel ratio by using only the signal of the
oxygen sensor (front) installed on the front side of the catalytic converter.
Detonation sensor
Switches the ignition timing from ignition timing for high octane to ignition timing for
standard octane fuel.