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Components
Exhaust camshaftOCVFinger follower & HLA
Intake camshaftIntake camshaft CVVT
gearCamshaft position
sensor
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1. OVERVIEW
The ignition system is to supply high voltage generated from the ignition coil to the spark plug. The
G20DF engine is equipped with the independent type direct ignition system that the ignition coil is
installed in each cylinder.
The basic ignition timing in each cylinder is determined by the signals from camshaft position sensor and
crankshaft position sensor.
This ignition system controls the electronic ignition timing received from the engine ECU. To control the
ignition timing precisely, the ECU use the information below:
Engine load
Coolant temperature
Intake air temperature
Engine rpm
Camshaft position sensor (CPS)
Crankshaft position sensor (CKS) -
-
-
-
-
-
If the signal from the camshaft position sensor is not delivered to the engine ECU, the ignition coil and
fuel system cannot be operated.
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2. COMPONENTS
Ignition coil
Camshaft position
sensorKnock sensorInjector
Spark plug
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Purge control
solenoid valve
G20DF engine
ECUCoolant Temp
sensorCamshaft position
sensor
Crankshaft position
sensor
T-MAP sensorVIS solenoid valveElectronic throttle
bodyMagnetic trigger
ring
Front oxygen
sensor
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Rear oxygen
sensor
2) Components for ECU Input
Coolant temperature
sensorCamshaft position
sensorCrankshaft position
sensor
Front oxygen sensor
Knock sensor
G20DF Engine ECUElectronic throttle
body
Refrigerant pressure sensor
Clutch pedal signal
Blower switch signal
Brake pedal signal
CAN
ABS & ESP
Instrument cluster
TCU -
-
-
Oil pressure
switchOil pressure warning lamp
T-MAP sensor
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3) Injection Volume Control
(1) Overview
To keep the best engine conditions and to reduce the emission gas, ECU determines the injection
volume and timing.
(2) Components
Input Components
Accelerator pedal
position sensorFront oxygen
sensorCoolant temperature
sensorCrankshaft position
sensor
Camshaft position
sensorKnock sensorT-MAP sensorElectronic throttle
body
Output Components
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Coolant temperature
sensor
4) Ignition System Control
(1) Overview
G20DF engine is equipped with the single ignition system. Each spark plug is operated independently
by the ECU and one ignition coil and spark plug are provided for each cylinder.
(2) Components
Input Components
Crankshaft position
sensorAccelerator pedal position
sensor
Knock sensorCamshaft position
sensorElectronic
throttle body
Output Components
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(4) Features
Determines the ignition timing according to input signal
The ECU always analyzes the following elements when determining the ignition timing. 1.
Crankshaft position sensor
Camshaft position sensor
Coolant temperature sensor
Intake air temperature/air mass -
-
-
-
Warm-up of catalytic converter
The ignition timing is retarded for about 20 seconds to operate the catalytic converter according to the
operating temperature under the following conditions: 2.
The idle speed is increased by the idle speed control to help warming up of the catalytic converter -
-
Idle speed control
The ignition timing control can be performed faster than the control through the throttle valve.
Fuel cut-off in deceleration
The ignition timing is retarded temporarily to prevent abrupt increase of the torque when the
combustion is restarted.
Intake air temperature/coolant temperature
The ignition timing is retarded to prevent knocking if the intake air temperature or coolant temperature
is high. The ignition timing is retarded in the following cases. 3.
4.
5.
-
-
The ignition timing retard for intake air temperature and for coolant temperature is added up for
correction.
ESP/ASR control mode
The ignition timing is retarded to reduce engine torque as fast as possible under the ESP/ASR
control mode.
Knocking control
If knocking occurs in the cylinder, the ignition angle of the corresponding cylinder is retarded. The
6.
7.