engine SSANGYONG NEW ACTYON SPORTS 2012 Manual PDF

03-252210-01
3) Input/Output devices
Refer to Chapter "Engine Control". *

03-26
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.

04-4
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.

04-51719-00
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.

04-6
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

04-71719-00
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".

04-8
3. INPUT/OUTPUT OF INTAKE SYSTEM
For more information, refer to Chapter " Engine Control". *

04-10
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.

04-111719-00
LoadEngine speed Swirl valveAmount of
swirlRemarks
Low speed,
Low loadbelow 3,000
rpmClosed HeavyIncreased EGR ratio, better air-fuel
mixture (reduce exhaust gas)
High speed,
High loadover 3,000 rpm Open LightIncrease charge efficiency, higher
engine power
The variable swirl valve actuator operates
when turning the ignition switch ON/OFF
position to open/close the swirl valve. In this
period, the soot will be removed and the
learning for swirl valve position is performed.
Swirl: This is the twisted (radial) air flow along the cylinder wall during the intake stroke. This
stabilizes the combustion even in lean air-fuel mixture condition.
Swirl valve
3) Features
Swirl and air intake efficiency
To generate the swirl, the intake port should be serpentine design. This makes the resistance
in air flow. The resistance in air flow in engine high speed decreases the intake efficiency.
Eventually, the engine power is also decreased, Thus, the swirl operation is deactivated in high
speed range to increase the intake efficiency.
Relationship between swirl and EGR
To reduce Nox, it is essential to increase EGR ratio. However, if EGR ratio is too high, the PM
also could be very higher. And, the exhaust gas should be evenly mixed with newly aspired air.
Otherwise, PM and CO are dramatically increased in highly concentrated exhaust gas range
and EGR ratio could not be increased beyond a certain limit. If the swirl valve operates in this
moment, the limit of EGR ratio will be higher. -
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4) Relationship between swirl and fuel injection pressure
The injector for DI engine uses the multi hole design. For this vehicle, there are 8 holes in injector.
If the swirl is too strong, the injection angles might be overlapped and may cause the increased
PM and insufficient engine power. Also, if the injection pressure is too high during strong swirl, the
injection angles might be overlapped. Therefore, the system may decreases the fuel injection
pressure when the swirl is too strong.

05-4
2. CAUTIONS
Do not park the vehicle on flammable materials, such as grass, leaves and carpet.
Do not touch the catalyst or the exhaust gas ignition system when the engine is running.
If a misfire occurs in the combustion chamber or the emission of pollutant exceeds the
specified level, the catalyst can be damaged.
When servicing or replacing components of the exhaust system, makes sure that the
components are positioned at regular intervals from all other parts of the under body.
Be careful not to damage the exhaust system when lifting the vehicle from its side.
All components and body parts of the engine exhaust system should be inspected for crack,
damage, air hole, part loss and incorrect mounting location. Also check for any deformation
which can result in exhaust gas drawn into the vehicle.
Make sure that the exhaust pipe is cooled down sufficiently before working on it because it is
still hot right after the engine is stopped.
Wear protective gloves when removing the exhaust pipe. -
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