2012 SSANGYONG RODIUS engine coolant

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C. Idle Speed Controller
The idle speed controller consists of 2 principal modules:
The first module determines the required idle speed according to:
* The operating conditions of the engine (coolant temperature, gear engaged)
* Any activation of the electrical consumers (power steering, air conditioning, others)
* The battery voltage
* The presence of any faults liable to interface with the rail pressure control or the injection control. In
this case, increase the idle speed to prevent the engine from stalling.
The second module is responsible for providing closed loop control of the engine's idle speed by
adapting the minimum fuel according to the difference between the required idle speed and the
engine speed. -
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D. Flow Limitation
The flow limitation strategy is based on the following strategies:
The flow limitation depending on the filling of the engine with air is determined according to the
engine speed and the air flow. This limitation allows smoke emissions to be reduced during
stabilized running.
The flow limitation depending on the atmospheric pressure is determined according to the engine
speed and the atmospheric pressure. It allows smoke emissions to be reduced when driving at
altitude.
The full load flow curve is determined according to the gear engaged and the engine speed. It
allows the maximum torque delivered by the engine to be limited.
A performance limitation is introduced if faults liable to upset the rail pressure control or the
injection control are detected by the system. In this case, and depending on the gravity of the fault,
the system activates: -
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Reduced fuel logic 1: Guarantees 75 % of the performance without limiting the engine speed.
Reduced fuel logic 2: Guarantees 50 % of the performance with the engine speed limited to
3,000 rpm.
Reduce fuel logic 3: Limits the engine speed to 2,000 rpm.
The system chooses the lowest of all values.
A correction depending on the coolant temperature is added to the flow limitation. This correction makes
it possible to reduce the mechanical stresses while the engine is warming up.
The correction is determined according to the coolant temperature, the engine speed and the time which
has passed since starting.
E. Superchager Flow Demand
The supercharge flow is calculated according to the engine speed and the coolant temperature. A
correction depending on the air temperature and the atmospheric pressure is made in order to increase
the supercharge flow during cold starts. It is possible to alter the supercharge flow value by adding a flow
offset with the aid of the diagnostic tool

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F. Pilot Flow Control
The pilot flow represents the amount of fuel injected into the cylinder during the pilot injection. This
amount is determined according to the engine speed and the total flow.
A first correction is made according to the air and water temperature.
This correction allows the pilot flow to be adapted to the operating temperature of the engine. When
the engine is warm, the ignition time decreases because the end-of-compression temperature is
higher. The pilot flow can therefore be reduced because there is obviously less combustion noise
when the engine is warm.
A second correction is made according to the atmospheric pressure. -
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During starting, the pilot flow is determined on the basis of the engine speed and the coolant
temperature.
G. Cylinder Balancing Strategy
Balancing of the point to point flows ▶
The pulse of each injector is corrected according to the difference in instantaneous speed measured
between 2 successive injectors.
The instantaneous speeds on two successive injections are first calculated.
The difference between these two instantaneous speeds is then calculated.
Finally, the time to be added to the main injection pulse for the different injectors is determined.
For each injector, this time is calculated according to the initial offset of the injector and the
instantaneous speed difference.
Detection of an injector which has stuck closed ▶
The cylinder balancing strategy also allows the detection of an injector which has stuck closed. The
difference in instantaneous speed between 2 successive injections then exceeds a predefined threshold.
In this case, a fault is signaled by the system.

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C. Learning Conditions
Idle MDP learning Drive MDP learning
Coolant temperatureover 60℃ over 60℃
Vehicle speedIdling over 50km/h (over 5 seconds)
Engine rpm2,000 to 2,500 rpm
Fuel temperature0 < Fuel temperature < 80℃
Learning2 times for each cylinder (every 5
seconds)2 times for each cylinder
(every 5 seconds)
If MDP learning is not properly performed, engine vibration and injection could be occurred.
MDP learning should be performed after replacing ECU, reprogramming and replacing injector. -
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D. Injector characteristic curve for rail pressure
The fuel injection curve is also called injection characteristic curve as shown above. The amount of
injected fuel is proportional to the square root of injection period and rail pressure.

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(8) Swirl control
A. Overview
Variable swirl valve ▶
The strong swirl caused by intake air is important element for anti-locking function in diesel engine. The
swirl control valve partially closes the intake port to generate the swirl according to the engine conditions.
When the engine load is in low or medium range, the swirl could not be generated because the air flow is
slow. To generate strong swirl, there are two passages in intake manifold, and one of them has the valve
to open and close the passage. When the valve closes the passage, the air flow through the another
passage will be faster, and the strong swirl will be generated by the internal structure of the passage. This
swirl makes the better mixture of air and fuel, eventually the combustion efficiency in combustion
chamber could be improved. This provides the enhanced fuel consumption, power and EGR ratio.
Components ▶
HFMCrankshaft position sensorVariable swirl valve
Coolant temperature
sensorAccekerator pedal
moduleD20DTR ECU

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Electric throttle
bodyAccelerator
pedal
moduleD20DTR
ECU
(9) EGR control
A. Overview
The EGR (Electric-Exhaust Gas Recirculation) valve reduces the NOx emission level by recirculating
some of the exhaust gas to the intake system.
To meet Euro-V regulation, the capacity and response rate of E-EGR valve in D20DTR engine have
been greatly improved. The EGR cooler with high capacity reduces the Nox, and the bypass valve
reduces the CO and HC due to EGR gas before warming up.
Also, the engine ECU adjusts the E-EGR opening by using the air mass signal through HFM sensor. If
the exhaust gas gets into the intake manifold when the EGR valve is open, the amount of fresh air
through HFM sensor should be decresed.
B. Components
E-EGR cooler
Coolant
temperature
sensorOxygen sensor
HFM (intake
air
temperature)
Crankshaft
position
sensorE-EGR valve
T-MAP
sensor

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D. Bypass control for EGR cooler
Cooler temperature ▶
<007e008f008c00950047009b008f008c0047008a00960096009300880095009b0047009b008c00940097008c00990088009b009c0099008c00470090009a00470089008c00930096009e0047005e00570b4500530047009b008f008c0047008c009f008f00
88009c009a009b0047008e0088009a00470090009a00470089>ypassed the EGR cooler.
Exhaust gas temperature ▶
<007e008f008c00950047009b008f008c0047008c009f008f0088009c009a009b0047008e0088009a0047009b008c00940097008c00990088009b009c0099008c00470090009a00470089008c00930096009e0047005a005700570b4500530047009b008f00
8c0047008c009f008f0088009c009a009b0047008e0088009a> is bypassed the EGR cooler.
Otherwise, PM could be increased due to too low exhaust gas temperature.
E. Control elements for EGR system
Accelerator pedal (engine load) - Indicates the driver's intention and engine load. If the load goes up,
the EGR ratio is decreased.
T-MAP (boost pressure map stored in ECU) - Compensates the difference in boost pressure by
adjusting EGR ratio.
Engine rpm - Used as the signal for determining EGR operating range.
Coolant temperature - When the coolant temperature is low, NOx is decreased but PM could be
increased. So, to reduce PM, decrease EGR ratio when the coolant temperature is low.
Intake air mass and temperature - HFM sensor measures the intake air mass to calculate the actual
EGR volume. If the air mass is larger than programmed value in map, EGR ratio will be higher.
EGR position sensor - Detects the actual opening angle of EGR valve and performs feedback
function according to PWM control by ECU.
Wide band oxygen sensor - Detects the oxygen volume in exhaust gas to check if the EGR ratio is
proper.
Electronic throttle body - Keeps EGR ratio to optimized level by controlling the throttle body in EGR
operating range (decreasing pressure in intake manifold). -
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(10) E-VGT control
A. Overview
E-VGT (Electric-Variable Geometry Turbine) turbocharger system in D20DTF engine uses the venturi
effect that controls the flow rate of exhaust gas by adjusting the passage in turbine housing. The newly
adopted DC motor actuator (E-actuator) controls the E-VGT system more precisely and faster. To get
the high operating power from turbine, the ECU reduces the exhaust gas passage In low speed range
and increases it in high speed range.
B. Components
HFM (intake air
temperature)
Front EGT
sensor
E-VGT actuatorAccelerator pedal
module
Crankshaft
position
sensorOxygen sensor
T-MAP sensor
Coolant
temperature
sensor
D20DTR ECU

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D. E-VGT system control
Turbocharger system operates the E-VGT actuator according to the signals for engine epm, accelerator
pedal position, atmospheric pressure, T-MAP, coolant temperature and intake air temperature.
Turbocharger actuator is performed PWM control by ECU.
In general, the boost pressure feedbacks the turbocharger operation and the boost temperature is used
for calculating the precise density.
E-VGT provides higher engine power with faster reaction speed compared to conventional VGT.
Operating wave Vane Control
Low
speed
rangeIn low speed range:
retract the vane to
increase boost
pressure. The vane
has low (-) duty, and
the unison ring
moves to retract the
vane in weak PWM
signal.
High
speed
rangeThe unison ring
moves to extend the
vane in strong PWM
signal. Maximum
pressure is 3 bar and
the system controls it
according to the input
signals.