2008 MITSUBISHI LANCER EVOLUTION X relay

EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-12
EVAPORATIVE EMISSION PURGE SOLENOID
An evaporative emission purge solenoid is installed in the
intake manifold.The evaporative emission purge solenoid con
-
trols the intake volume of fuel vapor gas from the canister. The
evaporative emission purge solenoid is a duty control type
solenoid valve. When current is not passing through the coil,
nipple A is kept airtight and fuel vapor gas cannot be sucked in.
When current passes through the coil, air can pass between
nipple A and B and fuel vapor gas is sucked in. ECM changes
the ON duty ratio according to engine's operating condition to
control the intake volume of fuel vapor gas.
EXHAUST GAS RECIRCULATION (EGR) SYSTEM M2171000300122
When the combustion gas temperature becomes
high, generation of the environment polluting NOx
(nitrogen oxides) increases rapidly. EGR system is
used to decrease the volume of NOx generated.
EGR system re-circulates exhaust gas inside the
intake manifold. It increases specific heat of the com
-
bustion gases and reduces combustion speed to lower the combustion temperature and reduce the
volume of NOx generated. ECM calculates the EGR
introduction volume according to engine operating
conditions and controls the EGR valve opening angle
at optimum. Also, immediately after the ignition
switch ON signal is input, it drives fully closed step
-
per motor and performs initialization.
AK604745AC
B To canister
To intake manifoldA
AK602245AD
12V
ONOFF
0V100 ms
Evaporative
emission
purge solenoidFrom MFI relay
ECM
AK502987AE
ECMMass airflow sensor
Intake air temperature sensor
Manifold absolute
pressure sensor
Engine coolant
temperature sensor
Throttle position sensor
Crankshaft position sensor BatteryEGR valve
(stepper motor)

EMISSION CONTROL
ENGINE AND EMISSION CONTROL17-13
EXHAUST GAS RECIRCULATION (EGR) VALVE
An EGR valve is installed in the EGR valve support.The EGR
valve controls EGR flow volume using the stepper motor
method and reduces exhaust gas (NOx) and fuel consumption.
The EGR valve drives the stepper motor based on the signal
from ECM. When stepper motor rotor turns in clockwise or
anti-clockwise direction, the shaft fitted with a rotor and a screw
expands and contracts and the movement of the shaft causes
the valve to go up and down. Thus, EGR path gap is controlled
minutely. The stepper motor turns 15
° per step. The stepper
motor turns forward or back only up to the angle dictated by the
number of pulse signals (number of steps) from the ECM. In
other words, increase and decrease of the EGR flow volume
depends on the number of signals (number of steps) from
ECM. ECM changes current flow to the 4 coils (A, B, C, D) in
the stepper motor in sequence according to the phase pattern
in the following chart in order to turn the stepper motor rotor.
Open valve changes phase in order of 0
→ 1 → 2 → 3 → 0. Close
valve changes phase in order of 3
→ 2 → 1 → 0 → 3.
Phase
numberStepper motor coil
Coil ACoil BCoil CCoil D
0ONOFFOFFON
1ONOFFONOFF
2OFFONONOFF
3OFFONOFFON
AK604144
Coil
Shaft
Valve Outlet
Inlet
Rotor
Magnet
AB
AK604145
From MFI relay
EGR valve
(stepper motor)
ECM Coil
ACoil
BCoil
CCoil
DFlow rate
Step
AB

13A-1
GROUP 13A
MULTIPORT FUEL
SYSTEM (MFI)
CONTENTS
GENERAL DESCRIPTION. . . . . . . . .13A-2
CONTROL UNIT. . . . . . . . . . . . . . . . .13A-6
SENSOR. . . . . . . . . . . . . . . . . . . . . . .13A-8
ACTUATOR . . . . . . . . . . . . . . . . . . . .13A-23
FUEL INJECTION CONTROL . . . . . .13A-29
IGNITION TIMING AND CONTROL FOR
CURRENT CARRYING TIME . . . . . .13A-35
THROTTLE VALVE OPENING ANGLE
CONTROL AND IDLE SPEED

CONTROL . . . . . . . . . . . . . . . . . . . . .13A-38
MIVEC (Mitsubishi Innovative Valve
Timing Electronic Control System) .13A-40
MULTIPORT FUEL INJECTION (MFI)
RELAY CONTROL . . . . . . . . . . . . . . .13A-45
FUEL PUMP RELAY CONTROL . . . .13A-46
STARTER RELAY CONTROL . . . . . .13A-47
HEATED OXYGEN SENSOR HEATER
CONTROL . . . . . . . . . . . . . . . . . . . . . .13A-49
A/C COMPRESSOR RELAY
CONTROL . . . . . . . . . . . . . . . . . . . . . .13A-50
GENERATOR CONTROL . . . . . . . . . .13A-51
EVAPORATIVE EMISSION CONTROL
SYSTEM INCORRECT PURGE FLOW
MONITOR . . . . . . . . . . . . . . . . . . . . . .13A-52
EXHAUST GAS RECIRCULATION
CONTROL . . . . . . . . . . . . . . . . . . . . . .13A-53
CONTROLLER AREA NETWORK
(CAN) . . . . . . . . . . . . . . . . . . . . . . . . .13A-53
EVAPORATIVE EMISSION PURGE
CONTROL . . . . . . . . . . . . . . . . . . . . . .13A-53
HC TRAP CATALYTIC CONVERTER
DETERIORATION MONITOR . . . . . . .13A-53
ON-BOARD DIAGNOSTICS . . . . . . . .13A-53

GENERAL DESCRIPTION
MULTIPORT FUEL SYSTEM (MFI)13A-3
System Block Diagram
AK604116
Mass airflow sensor
Intake air temperature sensor
Intake camshaft position
sensor
Exhaust camshaft position
sensor
Crankshaft position sensor Throttle position sensor (main)
Throttle position sensor (sub)
Accelerator pedal position
sensor (sub) Accelerator pedal position
sensor (main) Engine coolant temperature
sensor Manifold absolute pressure
sensor
Heated oxygen sensor (front)
Heated oxygen sensor (rear)
Power steering pressure
switch Engine oil pressure switch Generator L terminal
Ignition switch-ST
Power supply Ignition switch-IG
CAN communication
(input signal)
· A/C switch
· Vehicle speed
· Fuel level sensor
· Transmission range switch
Fuel tank differential pressure
sensor Heated oxygen sensor
(3rd)*
Knock sensor
Generator FR terminal
Fuel tank temperature sensor
Vehicle speed sensor Engine control unit Barometric pressure sensor
[1] Fuel injection control
[2] Ignition timing control
[3] Throttle valve opening angle
control and idle speed control
[4]
MIVEC (Mitsubishi Innovative
Valve timing Electronic Control
system)
[5] Power supply control
(Power supply to sensor,
actuator)
[6] Fuel pump relay control
[7] Starter relay control
[8] Heated oxygen sensor heater
control
[9] A/C compressor relay control
[10] Generator control
[11] Evaporative emission purge
control
[12] EGR control
[13] Diagnosis output
[14] RAM data transmission
CAN communication
(output signal) Intake engine oil control
valve
A/C compressor relay No. 2 injector
No. 3 injector
No. 4 injector
Heated oxygen sensor (front)
heater
Heated oxygen sensor (rear)
heater Throttle actuator control
motor
Throttle actuator control
motor relay No. 1 injector
No. 1 ignition coil
No. 2 ignition coi
No. 3 ignition coi
No. 4 ignition coi
Fuel pump relay
Generator G terminal Heated oxygen sensor (3rd)
heater*
Multiport fuel injection (MFI)
relay Exhaust engine oil control
valve
Evaporative emission ventilation
solenoid Evaporative emission purge
solenoid
EGR valve (stepper motor)*
Starter relay
AB
Sensor, switch Engine control module (ECM) Actuator
NOTE
*1: California

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-8
SENSORM2132001000565.
MASS AIRFLOW SENSOR
Mass airflow sensor is installed in the air intake hose. Mass air-
flow sensor is composed of an extremely small heatsensing
resistor. The mass airflow sensor controls the amount of elec
-
tric current flowing into the heat sensing resistor to keep the
heat sensing resistor at a constant temperature to the intake air
temperature. The faster the air flow speed, the higher the mass
flow rate.Because the amount of heat transfer from the heat
sensing resistor to the air increases, the mass airflow sensor
increases the amount of electric current to the heat sensing
resistor. Thus, the amount of electric current increases in
accordance with the air mass flow rate. The mass airflow sen
-
sor measures the air mass flow rate by detecting the amount of
electric current. The mass airflow sensor amplifies the detected
electric current amount and outputs it into the ECM. ECM uses
this output current and engine speed to calculate and decide
basic fuel injection time. Sensor properties are as shown in the
figure.
.
INTAKE AIR TEMPERATURE SENSOR
Intake air temperature sensor is built in to the mass airflow sen-
sor. Intake air temperature sensor detects intake air tempera-
ture through thermistor's resistance change and outputs the
voltage according to intake air temperature to ECM. ECM uses
this output voltage to compensate fuel injection control and
ignition timing control. Sensor properties are as shown in the
figure.
AK602252AC
Sensing areaSilicon substrate
Heat sensing
resistor
Intake air
Diaphragm
AK602221AG
From MFI relay
Mass airflow sensorECMOutput current mA
Mass flow g/s
AK602253AC
Sensory part
(thermistor)

SENSOR
MULTIPORT FUEL SYSTEM (MFI)13A-15
This allows ECM precise feedback control to get theoretical
air-fuel ratio with best cleaning efficiency of 3-way catalytic con
-
verter.
.
CRANKSHAFT POSITION SENSOR
A crankshaft position sensor is installed on the right side of the
cylinder block. The crankshaft position sensor monitors rotation
of crankshaft sensing ring (36 teeth including 3 missing teeth)
installed on the crankshaft and converts to voltage (pulse sig
-
nal) that is output to ECM. ECM uses crankshaft position sen-
sor's output pulse to detect crankshaft position.
.
AK602263AC
100
0HC
CONOx 50 Purge ratio
Theoretical air fuel ratio
AK602576AC
From MFI relay
Heated xygen sensor
Heater
Zirconia elementECM
0.5V
AK602737AC
Crankshaft
position
sensor Crankshaft sensing ring
(36 teeth including 3 missing teeth)