Page 210 of 600
0000-00
D20DT Engine Remarks
To enhance the EGR performance by
making the temperature of exhaust
gas into the intake manifold down, the
EGR cooler has been introduced. *EGR cooler
EGR GasCoolant
The throttle body and boost pressure
sensor have been installed on the
intake manifold. *
Intake manifold
Throttle
bodyBoost pressure sensor
Cylinder head
Coolant portTo enhance the cooling performance,
the coolant port has been introduced. *
To enhance the cooling performance,
the coolant passage has been made
in the cylinder block. *
Cylinder head gasket
Coolant passage
Page 212 of 600

1. FUEL FLOW OF D20DT (EURO 4) ENGINE
According to input signals from various sensors, engine ECU calculates driver's demand (position of the
accelerator pedal) and then controls overall operating performance of engine and vehicle on that time. ECU
receives the signals from sensors via data line and then performs effective engine air-fuel ratio controls
based on those signals. Engine speed is measured by crankshaft speed (position) sensor and camshaft
speed (position) sensor determines injection order and ECU detects driver's pedal position (driver's
demand) through electrical signal that is generated by variable resistance changes in accelerator pedal
sensor. HFM (Hot Film Air Mass) sensor detects intake air volume and sends the signals to ECU.
Especially, the engine ECU controls the air-fuel ratio by recognizing instant air volume changes from air flow
sensor to decrease the emissions (EGR valve control). Furthermore, ECU uses signals from coolant
temperature sensor and air temperature sensor, booster pressure sensor and atmospheric pressure sensor
as compensation signal to respond to injection starting, pilot injection set values, various operations and
variables.
Page 213 of 600
0000-00
HP PumpFuel Line
Injector (7-way Injection and C3I Coding)Fuel filter Priming Pump
Common Rail
2. COMPONENTS OF FUEL SYSTEM
Fuel nozzle
holes (7)
Injector
Fuel pipe
High pressure fuel pip Fuel rail pressure sensor
Fuel filter
Connector
Priming
pump
Fuel from
HP pumpFuel filter
HP pumpFuel tank
Fuel tank
Common rail
Fuel return
port
Low pressure
fuel supply port
Venturi
High pressure
fuel supply port
(orifice included)
Fuel
temperature
sensor
IMV valve
Fuel return
port
IMV
connector
Page 216 of 600
HFM Sensor (ver. 6.0)VGT Turbo Chargera
Uncompressed air
Air coeaner Turbo
charger
Temperature
sensor
Pretension
graph
Ambient air
Air cleaner
Compressed air
1. INTAKE SYSTEM LAYOUT
The intake system is equipped with an electric throttle body which includes a flap. This flap is controlled
by an electrical signal to cut off the intake air entering to the engine when the ignition switch is turned off.
And, the improved HFM sensor has been adopted to control the intake air volume more precisely.
Exhaust manifold
Air coeaner
Intercooler Exhaust gas
VGT control actuator
Page 217 of 600
0000-00
Intercooler
Booster Pressure SensorIntake Manifold
Ground Supply power
Output
voltageTo corresponding
cylinders Coolant
port
Compressed
air
EGR gas
Engine stopped:
flap closed Normal: flap open
Intake duct
Intake duct
Intake manifold
(Throttle body)
Turbo charger
Throttle body
Page 221 of 600

1533-01
1. OVERVIEW FOR CDPF (EURO IV)
The CDPF (Catalyst & Diesel Particulate Filter) was installed to the Rexton II D27DTP engine previously.
However, it is now installed to the all 2009 DI engine models, except the Actyon Sports. The DI engine
type sinstalled to Rexton are D27DTP, D27DT and D20DT, and their CDPF, related sensor and
operation logic are the same.This section describes the CDPF system (based on Euro IV) which is
installed to the Rexton II D27DTPengine (older model).
1) General Description
2) Compatibility of CDPF System by Vehicle Model
Rexton II: Same CDPF system for D27DTP and D27DT engines (including its components)
Kyron & Actyon: Same CDPF system for D27DT and D20DT engines (including its components)
The CDPF assemblies installed to the Euro IV D27DTP Rexton II and 2009 Rexton II are
different in their mounting layout, but their front/rear exhaust temperature sensors and
differential pressure sensors are same. -
3) System Met with EURO IV Regulations
The Ssangyong vehicles installed with the D27DT engine manufactured from July 2007 to December
2007 comply with the EURO IV regulations. Modified components from the old engine model are as
follow:
- E-EGR valve
- EGR cooler
- Engine ECU (Ver. 3.2)
- HFM senso
- C3I injector
- Electronic throttle valve (body)
- Other engine mounting components
For details about the modified components and system related to the EURO IV regulations, refer to the
2008 Rodius engine service manual.
Page 222 of 600

Under air cleaner in right side
of engine compartment
2. CDPF (EURO IV) SYSTEM
The CDPF system is only installed to the D27DT engine, and the major changes comparing to the
previous D27DT engine is as follows:
CDPF (Catalyst & Diesel Particulate Filter) and Sensors
Front exhaust gas
temperature sensor
CDPF Exhaust Gas Temperature Sensor
The two temperature sensors
in-side the CDPF are installed
inexhaust manifold (front
exhaustgas temperature
sensor) and inDOC (rear
exhaust gas tempera-ture
sensor), and perform the fol-
lowing functions.Front Exhaust Gas Tempera-ture
Sensor:
Measures the exhaust gas tem-
perature of the exhaust manifold. As it
is installed in front of the VGT
turbocharger, it also monitors the
exhaust gas tempera-ture coming to
the turbocharger. If the temperature of
the exhaust gas flowing to the
turbocharger is higher than the
specification, the engine lowers the
exhaust gas temperature.Rear Exhaust Gas Tempera-
ture Sensor:
Measures the increased ex-
haust gas temperature after
the oxidation process of DOC.
If the temperature is below
amount is increased to
increase the temperature.
As the soot is filtered in the CDPF, the pressure between the front side and the rear side of the filter is
different from each other. If the amount of soot is over 28 g, the soot is burnt in the CDPF. The
combustion is determined depending on the pressure difference, temperature of exhaust gas and
Page 223 of 600

1533-01
Throttle Body
CDPF system controls the amount of intake air by controlling the
electronic throttle body. The electronic throttle body has the
following main functions.
CDPF control - added a function that increases the exhaust gas
temperature by closing the throttle valve flap to minimize the intake
air amount by the fuel injection amount during the CDPF
regeneration range with the low engine load range.
ON/OFF control - prevents the engine from turning off with
vibration and noise by closing the throttle body flap to block the
intake air when the engine is stopped.
Duty control - controls the valve inside the throttle body to burn
more EGR gas in the EGR valve operating range.
VGT Turbocharger and Front Exhaust Gas Temperature Sensor
Turbocharger may become weaker if high tem-
perature exhaust gas passes through the tur-
bocharger for DPF regeneration process.
The front exhaust gas temperature sensor moni-tors
the temperature of the exhaust gas that flows into the
turbocharger.
If the temperature of the exhaust gas that passes
through the exhaust manifold is higher than the
specification, the ECU decreases the fuel injection
amount and increases the EGR gas intake amount to
decrease the exhaust gas temperature.Front exhaust gas
temperature sensor