Page 369 of 600
Maximizes the intake air charging efficiency (Approx. 15%) -Optimizes the exhaust gas flow rate by controlling the vanes inside the turbine housing with the E-
Actuator. 1.
(2) E-VGT Actuator (Electric-Actuator)
Target temperature and airflow control -Enhanced emmission control: By temperature control with CDPF system 1.
(1) Performance (for EURO V)
Has a faster response time than the conventional vacuum actuator. 2.
Improved low speed torque, high speed power and fuel economy.
Improved acceleration performance with rapid response time of vane. -
-
2) Features
Features
BenefitsFolding and unfolding of the vane
is controlled electrically
Easy to get low speed air volume
Rapid response time
Electric control -
-
-
-
Improved low speed torque and
power
Reduced exhaust gas
Improved fuel consumption
Improved acceleration
performance -
-
-
-
Page 397 of 600
1. OVERVIEW
The pre-heating system for D20DTR engine has the glow plug to the cylinder head (combustion
chamber), and improves the cold start performance and reduces the emission level.
The pre-heating resistor (air heater) is used to heat the intake air.
This enables the diesel fuel to be ignited in low temperature condition.
The ECU receives the information such as, engine rpm, coolant temperature, engine torque, etc.,
through CAN communication during pre-heating process; and the pre-heating control unit controls the
pre-heating, heating during cranking and post-heating by the PWM control.
Glow plug
Glow indicatorEngine ECU (D20DTR)
Glow plug control unit
(GCU)
Page 426 of 600
2. CAUTIONS
Standard pattern of soot accumulation
(1) Abnormal Soot Accumulation (2) Normal Soot Combustion
Cautions to protect the catalyst filter
Use the designated fuel only.
Observe the recommended service intervals of engine oil.
Check the engine oil level frequently and add if necessary.
Do not idle the vehicle unnecessarily.
Do not turn off the engine while the vehicle is running.
Do not shift the gear selector lever to neutral when going downhill.
Do not use improper engine oil or fuel additives.
Do not drive for a long time when the warning lamp is illuminated.
Make sure no flammable material, such as dry grass or tissue paper, contacts with the catalyst filter
while the vehicle is parked.
For the vehicles used in urban traffic, driving on the expressways for more than 1 hour at least once
per week is needed so that the PM inside CDPF isn't collected to one side only. -
-
-
-
-
-
-
-
-
-
Page 427 of 600

2412-02
The CDPF system enters the regeneration mode
when the driving distance becomes approx. 600
to 1,200 km (may differ by the driving condition
and driving style). Then, the engine ECU
performs the CDPF regeneration operation.
However, the driver is not informed with this
operation by any engine warning lamp or vehicle
signal, so he/she may not detect this operation.
The control logic at the post-injection dur-ing the
regeneration process is to increase the fuel
injection volume and control the intake air volume
(by the throttle body) in order to increase the
temperature of the exhaust gas. The driver may
not feel any particular difference from the vehicle.
Overload of CDPF (warning lamp blinking)
(3) Warning Lamp Related to CDPF
CDPF regeneration process (warning lamp NOT illuminated)
If the CDPF cannot reach the regeneration temperature due to low speed driving or other reason
during the regeneration process, the soot is continuously accumulated in the CDPF. When this
condition continues and the CDPF is overloaded with soot, the engine warning lamp blinks to inform
this situation to the driver.
In order to solve this problem, drive the vehicle at a speed of approx. 80 km/h for 15 to 20 minutes to
perform the CDPF regeneration process.
If the engine warning lamp on the instrument cluster blinks, the CDPF is overloaded. In this case,
perform the step 2. 1.
2.
3.
Turned off
Blinking
Page 430 of 600
Differential pressure
sensor
Calculates the amount of
PM collected by reading the
pressure difference between
before and after the CDPF.Engine ECU
DCM 3.7
Post-injectionThrottle
valve
Regulates the rate of air
intake.
CDPF
DOC+DPFFront temperature
sensor
Protects the turbocharger.Rear temperature sensor
Measures the temperature
of fuel combustion.
2. COMPONENT
For details, refer to section "Engine Control". *
Page 431 of 600
2412-02
3. INPUT/OUTPUT DEVICES
Front temperature sensor: This sensor is installed at the inlet of DOC and detects whether the
DOC can burn (oxidize) the post-injected fuel or not.
Rear temperature sensor: This sensor is installed at the inlet of DPF and monitors that the 1.
2.
post-injection is decreased.
amount of fuel post-injection is increased. -
-
Differential pressure sensor: This sensor checks the amount of PM collected by calculating the
pressure difference between before and after the CDPF.
Electric throttle valve: This valve reduces the intake air flow to raise the temperature of the exhaust
gas when the CDPF is operating during idling. 3.
4.
Page 432 of 600

4. POST-INJECTION AND AIR MASS CONTROL
A DPS (Differential Pressure Sensor) measures the pressure difference between before and after the
CDPF and detects whether the soot is collected in the CDPF or not. If PM is collected in the CDPF (In
this case the pressure difference between before and after the CDPF exceeds the specified value.
Normally, the system sends the signal when the driving distance becomes approx. 600 to 1,200 km), the
temperature of exhaust gas is increased and the post-injection is started for regeneration. The amount of
fuel post-injection is controlled by the exhaust gas temperature measured by the rear temperature
increase the regeneration temperature. Otherwise, the fuel injection amount is decreased or the fuel is
not injected.
When the engine is running with low load, the intake air amount is also controlled as well as fuel injection
amount. This function is used to increaser the combustion temperature by increasing the amount of fuel
post-injection with the lowest air amount within the specified control logic.
Page 433 of 600

2412-02
Front temperature sensor
Measures the temperature of
exhaust gas.
This sensor is located at the rear
side of exhaust manifold and
monitors the temperature of
combusted gas to prevent the
exhaust system from overheating.
When the temperature gets higher,
this sensor cuts off the fuel delivery
and controls the EGR to lower the
temperature.Rear temperature sensor
Measure the outlet
temperature of DOC.
This sensor is located at the
rear side of DOC and
monitors the overheating of
CDPF and post injection
volume.
Engine ECU (D20DTR)
Differential pressure sensor
Measures the difference between
inlet and outlet pressures of CDPF.
If the difference is higher than the
specified value when collecting the
PM, this makes the post injection for
forced recycling of PM.
T-MAP sensorIntake air
mass
Measures
the
excessive
amount of
PM.
Boos
t
pressure
/
temperature
Injector (C31)
Controls the post injection.
Electric throttle body
Controls the intake air mass.
HFM sensor
Wide band
oxygen senso
r