Mitsubishi Lancer Evolution IV, Workshop Manual

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MPI –
Troubleshooting
13-7
1-3 ERASING DIAGNOSIS CODES
(1) Turn the ignition switch to OFF.
(2) After disconnecting the battery cable from the battery (–) terminal for 10 seconds or more, reconnect
the cable.
(3) After the engine has warmed up, run it at idle for about 15 minutes.
1-4 FAIL-SAFE FUNCTION REFERENCE TABLE
When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled
by means of the pre-set control logic to maintain safe conditions for driving.
Malfunctioning item Control contents during malfunction
Air flow sensor (AFS) (1) Uses the throttle position sensor signal and engine speed signal (crank angle sensor
signal) to take reading of the basic injector drive time and basic ignition timing from
the pre-set mapping.
(2) Fixes the ISC servo in the appointed position so idle control is not performed.
Intake air temperature
sensor Controls as if the intake air temperature is 25
_
C.
Throttle position
sensor (TPS) No increase in fuel injection amount during acceleration due to the throttle position sensor
signal.
Engine coolant
temperature sensor Controls as if the engine coolant temperature is 80
_
C.
(This condition is maintained until the ignition switch is turned off even when the sensor signal
returns normal.)
Camshaft position
sensor (1) Injects fuel to all cylinders simultaneously for 4 seconds.
(However, after the ignition switch is turned to ON, the No. 1 cylinder top dead centre
is not detected at all.)
(2) Lets the fan motor (radiator and condensor) run at high speed.
Barometric pressure
sensor Controls as if the barometric pressure is 101 kPa {760 mmHg}.
Detonation sensor Switches the ignition timing from ignition timing for super petrol to ignition timing for standard
petrol.
Ignition coil, power
transistor Cuts off the fuel supply to cylinders with an abnormal ignition.
Alternator FR terminal Does not control the output of the alternator according to an electrical load. (works as a
normal alternator)
Misfire
(Evolution-V only) Cuts off the fuel to the misfiring cylinder if a misfire that could damage the catalyst is detected.