engine SSANGYONG NEW REXTON 2012 Owners Manual

Fuel tank
Fuel metering by sender
2. SYSTEM LAYOUT AND OPERATION
1) Layout
For sensor and actuator control logic, refer to Chapter "Engine Control".
Engine ECU (D20DTR)
Engine control by various
signals
Crankshaft position sensor
Measuring engine rpm
Injector (C3I)
Pre-injection, main injection,
after-injection by signals from
ECU
HFM sensor
Measuring intake air mass and
temperature
Camshaft position sensor
Determining injection order

2210-01
Accelerator pedal position
sensor
Detecting driver's intention
for speed up/down
Fuel rail assembly
Relieving the pulsation.
Measuring the fuel pressure.
Distributing the fuel to injectors.
Fuel filter assembly
Supplying clean fuel/fuel
heating/water separation by
priming pump
Plunger type HP pump (1,800 bar)
Vane type LP pump (6 bar)
T-MAP sensor
Measuring booster pressure
and temperature
High pressure pump
Generating high pressurized fuel and
supplying it according to engine rpm,
required volume, required pressure

2210-01
3) Input/Output devices
Refer to Chapter "Engine Control". *

The engine ECU calculates the accelerator pedal based on the input signals from various sensors, and
controls the overall operation of the vehicle.
The ECU receives the signals from various sensor through data line, and performs effective air-fuel ratio
control based on these signals.
The crankshaft speed (position) sensor measures the engine speed, and the camshaft speed (position)
sensor determines the order of injections, and the ECU detects the amount of the accelerator pedal
depressed (driver's will) by receiving the electrical signals from the accelerator pedal sensor.
The mass air flow sensor detects the volume of intake air and sends the value to the ECU.
The major function of the ECU is controlling air-fuel ratio to reduce the emission level (EGR valve control)
by detecting instantaneous air flow change with the signals from the mass air flow sensor.
Also, the ECU uses the signals from the coolant temperature & air temperature sensors, booster pressure
sensor, atmospheric pressure sensor to: a) determine injection starting point and set value for pilot
injection, and b) deal with various operations and variable conditions.

2. INSPECTION
1) Troubleshooting
When Abnormal Noises are Heard from the Engine Room
For the vehicle equipped with DI engine, if a learning noise occurs in each range or other noises
occur, the major cause of it is a faulty turbocharger assembly. But an interference issue, poor
tightness or loose in the intake and exhaust system also can cause those noises. This is mainly
because the operator didn't follow the instruction exactly when reconnecting the intake hoses and
pipes which were disconnected to check the system or replace the air cleaner. If the intake system is
free of any faults, check the EGR and PCV oil separator connected to the intake system.
The figure may be different from the actual engine. Therefore, read thoroughly below before replacing
the parts.
2) Abnormal Noise Caused by Poor Tightness of Intake System
When the DI engine is running, the air entered into the engine flows in the sequence as shown above. If
high intake pressure is applied to the loose or damaged part, a whistling noise may occur, the intake air
volume is measured incorrectly or the engine power is derated.

1719-00
3) Troubleshooting Sequence
The basic checks for intake system are as follows:
Basic Checks for Intake System
Make sure to replace or clean the air cleaner
element periodically. Otherwise, engine will be
derated or work abnormally because of low
intake air volume.
Unlike the fuel system, which is a closed
circuit, the intake system is an open circuit
system. Therefore any malfunction may occur
due to dust and dirt.
Most of the connections consist of hoses so
the system cannot withstand high temperature
and pressure. Also it can be deformed or
loosened easily because it is a clamp
mounting system. Thus, when checking the
engine, basic inspections, such as tightened
status check and visual inspection for hose,
etc., should be carried out in advance.
Other Checks for Intake System
If the intake system is free of any faults, check
for EGR and PCV oil separator.

1. OVERVIEW
The intake system for D20DTR engine is equipped with a 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. Because of this, the shape of the intake manifold has been changed and improved HFM
sensor is newly adopted to control the intake air volume more precisely.
2. COMPONENT
2330-01 Intercooler assembly
2313-15 HFM sensor
HFM sensor, version 6
*For more information, refer to Chapter "Engine
Control".
2313-01 Air cleaner assembly

1719-00
1719-02 Swirl control valve
Operating variably in accordance with the engine
load and rpm.* For more information, refer to
Chapter "Engine Control".
1719-01 Intake manifold
Passage for variable swirl valve and for intake air
1719-16 Electric throttle body
* For more information, refer to Chapter "Engine
Control".

3. INPUT/OUTPUT OF INTAKE SYSTEM
For more information, refer to Chapter " Engine Control". *

1) Types of swirl
Swirl: One cylinder has two intake air ports, one is set horizontally and
the other one is set vertically. Swirl is the horizontal air flows in cylinder
due to the horizontal intake air ports.
Tumble: Tumble is the vertical air flows in cylinder due to the vertical
intake air port
Squish: Squish is the air flows due to the piston head. Normally, this is
appears at the final process of compression. In CRDi engine, the
piston head creates the bowl type squish.
2) Swirl control
In DI type diesel engine, the liquefied fuel is injected into the cylinder directly. If the fuel is evenly
distributed in short period, the combustion efficiency could be improved. To get this, there should be
good air flow in cylinder. In general, there are two intake ports, swirl port and tangential port, in each
cylinder. The swirl port generates the horizontal flow and the tangential port generates the longitudinal
flow. In low/mid load range, the tabgential port is closed to increase the horizontal flow. Fast flow
decreases the PM during combustion and increases the EGR ratio by better combustion efficiency.