2012 SSANGYONG NEW REXTON fuel

2412-02
1) Oxidation of DOC
detects whether the DOC can burn (oxidize) the post-injected fuel or not, and sends the signal to the
and HC of the exhaust gas by redox reaction and also reduces small amount of PM.

2) Collecting PM of DPF
There is a filter installed in the DPF and the PM filtered by this filter is burned (regeneration) when the
temperature of exhaust gas is increased due to post-injection. The filter has a honeycomb-like structure
to capture the particulate matter and the inlet and outlet of each channel are closed alternatively. Once
the exhaust gas enters to the inlet of a channel, it is released from the outlet of the adjacent channel
through the porous wall because of the closed outlet of the first channel, and the PM is collected in the
first channel.
[Collecting PM of CDPF]
Normally, when the driving distance becomes approx. 600 to 1,200 km, enough amount of soot to
be burned is filtered and accumulated in the CDPF. The ECU increases the amount of fuel post-
burned. The soot is burned for 15 to 20 minutes (may differ by conditions).

4) Fuel Injection During CDPF Regeneration
Post injection
exhaust gas. The post injection does not make the actual output. The post injection activates the fuel by
injecting the fuel to the incompletely combusted gas after primary combustion. Through the process, the
PM and smoke in the exhaust gas could be reduced. There are totally 7 injections as shown in the
figure. However, all of 7 injections are not performed during driving because it decreases the fuel
economy. Totally 5 injections can be performed in one cycle. The injection method in D20DTR engine has three steps;
Pilot injection, Main injection, Post injection

7. CAUTIONS
1) Designated Engine Oil for CDPF (Low Ash Oil)
Need to use the designated engine oil for CDPF 1.
The smoke from the vehicle may generate the particle material in the ambient air. CDPF is the
device to reduce the smoke by collecting and recycling it. To ensure the performance of CDPF,
the designated engine oil should be used.
The smoke including combusted sulfur in fuel cannot be recycled in CDPF. This smoke
generates the ash, resulting in clogging the filter. -
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Advantages when using the designated engine oil for CDPF 2.
Reduces the amount of ash
Improves the fuel economy and reduces the CO2
Increases the life span of engine oil
Available for all engines (diesel and gasoline) -
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Problems when using non-designated engine oil for CDPF 3.
Decreases the life span of engine oil due to accumulated ash in DPF (around 30%)
Decreases the fuel economy due to friction resistance, exhaust gas resistance and frequent
recycling process of DPF -
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The fuel containing high sulfur may cause the same problems.
2) Do Not Use the Fuel Containing High Sulfur
Producing white smoke during recycling 1.
The sulfur in exhaust gas is changed to sulfate gas during exhaust process. This sulfate gas is
shown as white smoke. -
Producing odor during recycling 2.
The sulfur after oxidation may produce the odor. -
Accumulation of ash 3.
The sulfur accumulated in DPF cannot be recycled. It reduces the life span of DPF. -
3) White Smoke
The white smoke can be generated when the exhaust gas is recycled in DPF. There are two reasons as
below.
Saturated vapor
Sulfate -
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Fuel rail pressure
sensorEGR valve
Electric throttle bodyKnock sensor
(2 ea)
Coolant temperature
sensor
T-MAP sensorD20DTR ECU
E-VGT actuator
Water sensorGCU (Preglow control
unit)
E-EGR bypass valve
Fuel temperature
sensor

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Fuel rail pressure
sensor
(2) Components for ECU Input
CAN
- ABS & ESP
- GCU
- Instrument
cluster
- TCU
- STICSSwirl valve
position sensor
Differential
pressure sensorE-EGR valve
position sensorCamshaft position
sensorCoolant
temperature
sensor
Exhaust gas
temperature
sensorHFM sensorOxygen sensorT-MAP sensor
Crankshaft
position sensorAccelerator pedal
sensorThrottle position
sensorKnock sensor
-Auto cruise switch
- Rear right wheel
speed (without ABS)
- Refrigerant pressure
sensor
- Clutch pedal signal
- Blower switch signal
- Brake pedal signal
Water sensor

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2) ECU Control
(1) Function
a. ECU Function
ECU receives and analyzes signals from various sensors and then modifies those signals into
permissible voltage levels and analyzes to control respective actuators.
ECU microprocessor calculates injection period and injection timing proper for engine piston speed and
crankshaft angle based on input data and stored specific map to control the engine power and emission
gas.
Output signal of the ECU microprocessor drives pressure control valve to control the rail pressure and
activates injector solenoid valve to control the fuel injection period and injection timing; so controls
various actuators in response to engine changes. Auxiliary function of ECU has adopted to reduce
emission gas, improve fuel economy and enhance safety, comforts and conveniences. For example,
there are EGR, booster pressure control, autocruise (export only) and immobilizer and adopted CAN
communication to exchange data among electrical systems (automatic T/M and brake system) in the
vehicle fluently. And Scanner can be used to diagnose vehicle status and defectives.
water and electromagnetism and there should be no mechanical shocks.
To control the fuel volume precisely under repeated injections, high current should be applied instantly
so there is injector drive circuit in the ECU to generate necessary current during injector drive stages.
Current control circuit divides current applying time (injection time) into full-in-current-phase and hold-
current-phase and then the injectors should work very correctly under every working condition.
b. Control Function
Controls by operating stages
To make optimum combustion under every operating stage, ECU should calculate proper injection
volume in each stage by considering various factors.
Starting injection volume control
During initial starting, injecting fuel volume will be calculated by function of temperature and engine
cranking speed. Starting injection continues from when the ignition switch is turned to ignition
position to till the engine reaches to allowable minimum speed.
Driving mode control
If the vehicle runs normally, fuel injection volume will be calculated by accelerator pedal travel and
engine rpm and the drive map will be used to match the drivers inputs with optimum engine power. -
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(2) Fuel injection control
a. Multi injection
Fuel injection process consists of 3 steps: Main Injection, Pilot Injection, Post Injection
InjectionFunction
MainProduces engine power
Pilot 1Reduces PM by injecting before
main injection.AfterPM control
Pilot 2Reduces NOx and noise by
shortening main injection delay
due to flammability Post 1Reduces PM by enabling fuel
activation.
PreControls NOx emission level,
Combustion noise and
Stable idle Post 2Activates CDPF by increasing
exhaust gas temperature and
supplying reduction material
Pilot injectionMulti injection