2008 MITSUBISHI LANCER EVOLUTION X abs

GENERAL DESCRIPTION
MULTIPORT FUEL SYSTEM (MFI)13A-4
Control System Diagram

AK604117
Fuel level
sensorFuel tank Air
inlet
2 Exhaust engine
oil control valve
1 Intake engine
oil control valve4 Manifold absolute pressure sensor
2 Intake air
temperature sensor
1 Mass airflow sensor
6 Intake
camshaft
position
sensor
7 Exhaust
camshaft
position
sensor
3 Throttle position
sensor (main/sub)
5 Evaporative emission
purge solenoid
3 Throttle actuator
control motor
12 Fuel tank differential
pressure sensor
13 Fuel tank
temperature
sensor10 Heated oxygen sensor (front)
11 Heated oxygen
sensor (rear)
8 Crankshaft position sensor5 Engine coolant
temperature sensor
9 Knock sensor
4 Injector
Fuel pump Fuel pressure
regulator Evaporative
emission
canister
6 Evaporative
emission
ventilation
solenoid
1 Mass airflow sensor
2 Intake air temperature sensor
3 Throttle position sensor (main/sub)
4 Manifold absolute pressure sensor
5 Engine coolant temperature sensor
6 Intake camshaft position sensor
7 Exhaust camshaft position sensor
8 Crankshaft position sensor
9 Knock sensor
10 Heated oxygen sensor (front)
11 Heated oxygen sensor (rear)
12 Fuel tank differential pressure sensor
13 Fuel tank temperature sensor
Ignition switch-IG
Ignition switch-ST
Power supply
CAN communication (input signal)1 Intake engine oil control valve
2 Exhaust engine oil control valve
3 Throttle actuator control motor
4 Injector
5 Evaporative emission purge solenoid
6 Evaporative emission ventilation
solenoid
Ignition coil, ignition power transistor
Multiport fuel injection (MFI) relay
Fuel pump relay
Starter relay
Throttle actuator control motor relay
Generator G terminal
Heated oxygen sensor heater
A/C compressor relay
Diagnostic output
CAN communication (output signal) SenseAct
Engine oil pressure switch
Power steering pressure switch
Generator FR terminal
Generator L terminal
Vehicle speed sensor Accelerator pedal position sensor (main/sub)
Decide
ECM
(with barometric
pressure sensor)
AB

GENERAL DESCRIPTION
MULTIPORT FUEL SYSTEM (MFI)13A-5

AK604118
Fuel tank
Fuel level
sensor Air
inlet
2 Exhaust engine
oil control valve
1 Intake engine
oil control valve4 Manifold absolute pressure sensor
2 Intake air
temperature sensor
1 Mass airflow sensor
6 Intake
camshaft
position
sensor
7 Exhaust
camshaft
position
sensor
3 Throttle position
sensor (main/sub)
5 Evaporative emission
purge solenoid
3 Throttle actuator
control motor
12 Fuel tank differential
pressure sensor
13 Fuel tank
temperature
sensor11 Heated oxygen sensor (rear)
10 Heated
oxygen
sensor
(front)
12 Heated oxygen sensor (3rd)
8 Crankshaft position sensor5 Engine
coolant
temperature
sensor
9 Knock sensor
4 Injector
Fuel pump Fuel pressure
regulator Evaporative
emission
canister
6 Evaporative
emission
ventilation
solenoid
7 EGR valve
(stepper motor)
1 Mass airflow sensor
2 Intake air temperature sensor
3 Throttle position sensor (main/sub)
4 Manifold absolute pressure sensor
5 Engine coolant temperature sensor
6 Intake camshaft position sensor
7 Exhaust camshaft position sensor
8 Crankshaft position sensor
9 Knock sensor
10 Heated oxygen sensor (front)
11 Heated oxygen sensor (rear)
12 Heated oxygen sensor (3rd)
13 Fuel tank differential pressure sensor
14 Fuel tank temperature sensor
Ignition switch-IG
Ignition switch-ST
Power supply
CAN communication (input signal)1 Intake engine oil control valve
2 Exhaust engine oil control valve
3 Throttle actuator control motor
4 Injector
5 Evaporative emission purge solenoid
6 Evaporative emission ventilation
solenoid
7 EGR valve (stepper motor)
Ignition coil, ignition power transistor
Multiport fuel injection (MFI) relay
Fuel pump relay
Starter relay
Throttle actuator control motor relay
Generator G terminal
Heated oxygen sensor heater
A/C compressor relay
Diagnostic output
CAN communication (output signal) SenseAct
Engine oil pressure switch
Power steering pressure switch
Generator FR terminal
Generator L terminal
Vehicle speed sensor Accelerator pedal position sensor (main/sub)
Decide
ECM
(with barometric
pressure sensor)
AB

SENSOR
MULTIPORT FUEL SYSTEM (MFI)13A-9
.
MANIFOLD ABSOLUTE PRESSURE SENSOR
The manifold absolute pressure sensor is installed in the intake
manifold. Manifold absolute pressure sensor uses a piezo
resistive semiconductor to output the voltage according to man
-
ifold absolute pressure to ECM. ECM uses this output voltage
to compensate fuel injection volume according to manifold
absolute pressure. Sensor properties are as shown in the fig
-
ure.
.
AK602207
Intake air
temperature C (F)
AG
Resistance kΩOutput voltage V
Intake air temperature
sensor (thermistor)5V
Intake air
temperature C (F) ECM
AK602254 ACPressure Manifold absolute
pressure sensor
AK602206AH
5V
0
101 5V
GroundOutput voltage V
Pressure kPa (in.Hg) Manifold absolute
pressure sensorPower supply
Output signal
ECM

FUEL INJECTION CONTROL
MULTIPORT FUEL SYSTEM (MFI)13A-29
FUEL INJECTION CONTROLM2132003001036
Fuel injection volume is regulated to obtain the opti-
mum air-fuel ratio in accordance with the constant
minute changes in engine driving conditions. Fuel
injection volume is controlled by injector drive time
(injection time). There is a prescribed basic drive
time that varies according to the engine speed and intake air volume. ECM adds prescribed compensa
-
tions to this basic drive time according to conditions
such as the intake air temperature and engine cool
-
ant temperature to decide injection time. Fuel injec-
tion is done separately for each cylinder and is done
once in two engine rotations.
System Configuration Diagram
1. INJECTOR ACTUATION (FUEL INJECTION)
TIMING
Injector drive time in case of multiport fuel injection (MFI) is
controlled as follows according to driving conditions.
AK604128AB
ECM InjectorMass airflow sensor
Intake air temperature sensor
Manifold absolute
pressure sensor
Engine coolant
temperature sensor
Accelerator pedal position sensor
Knock sensor
Intake camshaft position sensor
Ignition switch-ST
Heated oxygen sensor (front, rear) Crankshaft position sensor

FUEL INJECTION CONTROL
MULTIPORT FUEL SYSTEM (MFI)13A-32
Fuel Injection Volume Control Block Diagram
.
AK602278AD
Mass airflow sensor
Crankshaft
position sensor
Heated oxygen
sensor
Engine coolant
temperature
compensation Engine coolant
temperature sensor
Manifold absolute
pressure sensorFuel pressure
compensation Barometric pressure
sensor
Battery voltage
compensation Battery voltageBasic fuel
injection time
determinationAir fuel ratio
compensation
(Predetermined
compensation)
Heated oxygen
sensor feedback
compensation
Injector Acceleration-
deceleration
compensation

FUEL INJECTION CONTROL
MULTIPORT FUEL SYSTEM (MFI)13A-33
[Injector basic drive time]
Fuel injection is performed once per cycle for each cylinder.
Basic drive time refers to fuel injection volume (injector drive
time) to achieve theoretical air-fuel ratio for the intake air vol
-
ume of 1 cycle of 1 cylinder. Fuel injection volume changes
according to the pressure difference (injected fuel pressure)
between manifold absolute pressure and fuel pressure (con
-
stant). So, injected fuel pressure compensation is made to
injector drive time for theoretical air-fuel ratio to arrive at basic
drive time.
Intake air volume of each cycle of 1 cylinder is calculated by
ECM based on the mass airflow sensor signal and crankshaft
position sensor signal. Also, during engine start, the map value
prescribed by the engine coolant temperature sensor signal is
used as basic drive time.
.
AK602279AC
Basic fuel
injection timeFuel injection pressure compensation Intake air amount per cycle per cylinder
Theoretical air-fuel ratio

FUEL INJECTION CONTROL
MULTIPORT FUEL SYSTEM (MFI)13A-34
[Injector drive time compensation]
After calculating the injector basic drive time, the ECM makes
the following compensations to control the optimum fuel injec
-
tion volume according to driving conditions.
List of main compensations for fuel injection control
.
[Fuel limit control during deceleration]
ECM limits fuel when decelerating downhill to prevent exces-
sive rise of catalytic converter temperature and to improve fuel
efficiency.
.
[Fuel-cut control when over-run]
When engine speed exceeds a prescribed limit (6,600 r/min),
ECM cuts fuel supply to prevent overrunning and thus protect
the engine. Also, if engine speed exceeds 4,000 r/min for 15
seconds while vehicle is stationary (no load), it cuts fuel supply
and controls the throttle valve opening angle to protect the
engine.
CompensationsContent
Heated oxygen sensor feedback compensationThe heated oxygen sensor signal is used for
making the compensation to get air-fuel ratio with
best cleaning efficiency of the 3-way catalytic
converter. This compensation might not be made
sometimes in order to improve drivability,
depending on driving conditions. (Air-fuel ratio
compensation is made.)
Air-fuel ratio compensationUnder driving conditions where heated oxygen
sensor feedback compensation is not performed,
compensation is made based on pre-set map
values that vary according to engine speed and
intake air volume.
Engine coolant temperature compensationCompensation is made according to the engine
coolant temperature. The lower the engine coolant
temperature, the greater the fuel injection volume.
Acceleration/ Deceleration compensationCompensation is made according to change in
intake air volume. During acceleration, fuel injection
volume is increased. Also, during deceleration, fuel
injection volume is decreased.
Fuel injection compensationCompensation is made according to the pressure
difference between atmospheric pressure and
manifold absolute pressure. The greater the
difference in pressure, the shorter the injector drive
time.
Battery voltage compensationCompensation is made depending on battery
voltage. The lower the battery voltage, the greater
the injector drive signal time.
Learning value for fuel compensationCompensation amount is learned to compensate
feedback of heated oxygen sensor. This allows
system to compensate in accordance with engine
characteristics.

IGNITION TIMING AND CONTROL FOR CURRENT CARRYING TIME
MULTIPORT FUEL SYSTEM (MFI)13A-35
IGNITION TIMING AND CONTROL FOR CURRENT
CARRYING TIME
M2132027100089
Ignition timing is pre-set according to engine driving
conditions. Compensations are made according to
pre-set values depending on conditions such as
engine coolant temperature, battery voltage etc. to
decide optimum ignition timing. Primary current con
-
nect/disconnect signal is sent to the power transistor
to control ignition timing. Ignition is done in sequence
of cylinders 1, 3, 4, 2.
System Configuration Diagram
AK502722AD
ECM MFI relay
Spark plugs Ignition
coils
Cylinder No. 1 2 3 4Battery
Mass airflow sensor
Intake air temperature sensor
Manifold absolute
pressure sensor
Engine coolant
temperature sensor
Intake camshaft position sensor
Exhaust camshaft position sensor
Crankshaft position sensor
Knock sensor
Ignition switch-ST Throttle position sensor