Turbo SSANGYONG NEW REXTON 2012 Owner's Manual

3) Inspection of Turbine
Thoroughly check the followings.
Must absolutely not operate the turbocharger with the compressor outlet and inlet opened as it could
damage the turbocharger or be hazardous during inspection.
Interference: In case where is trace of interference or smallest damage on the compressor wheel
means, most of times, that abrasion has occurred on the journal bearing. Must inspect after the
overhaul.
Oil Leakage: The reason for oil leakage at the compressor section is the air cleaner, clogged by
substances such as dust, causes the compressor inlet negative pressure. -
-
Rotating in high speed at no-load for extended period of time can cause oil leakage to the
compressor section as oil pressure within the center housing gets higher than pressure within the
compressor housing.
Overuse of engine break (especially in low gear) in down hill makes significantly low exhaust gas
energy compared to the time where great amount of air is required during idling conditions of the
engine. Therefore, amount of air in the compressor inlet increases but the turbocharge pressure is
not high, which makes negative a.
b.
No problem will occur with the turbocharger if above conditions are found in early stage but oil
leaked over long period of time will solidify at each section causing to breakout secondary defects.
Damages by foreign materials: In case where the compressor wheel is damaged by foreign materials
requires having an overhaul. At this time, it's necessary to check whether the foreign materials have
contaminated intake/exhaust manifold or inside of engine.

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4) Possible Causes of Defect
The following tries to understand the defects that can occur with vehicle installed with the turbocharger
and to manage the reasons of such defects.
In case where oil pan/oil pipe has been contaminated, oil filter is defected and where adhesive of
gaskets has been contaminated into the oil line. 1.

Defects caused by reasons other than that of the turbocharger. 4.

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3. TROUBLESHOOTING
The followings are cautions to take in handling defects of turbocharger, which must be fully aware of.
1) Cautions
After stopping the engine, check whether the bolts on pipe connecting section are loose as well as
the connecting condition of vacuum port and modulator, which is connected to the actuator.
During idling of the engine, check for leakage in the connecting section of pipe (hoses and pipes,
duct connections, after the turbocharger) by applying soap water. The leakage condition in the
engine block and turbine housing opening can be determined by the occurrence of abnormal noise o
f
exhaust.
By running the engine at idle speed, abnormal vibration and noise can be checked. Immediately stop
the engine when abnormal vibration and noise is detected and make thorough inspection whether
the turbocharger shaft wheel has any damages as well as checking the condition of connections
between pipes.
In case where the noise of engine is louder than usual, there is possibility of dampness in the areas
related with air cleaner and engine or engine block and turbocharger. And it could affect the smooth
supply of engine oil and discharge.
Check for damp condition in exhaust gas when there is sign of thermal discoloration or discharge of
carbon in connecting area of the duct.
When the engine rotates or in case where there is change in noise level, check for clogging of air
cleaner or air cleaner duct or if there is any significant amount of dust in the compressor housing.
During the inspection of center housing, inspect inside of the housing by removing the oil drain pipe
to check for sludge generation and its attachment condition at shaft area or turbine side.
Inspect or replace the air cleaner when the compressor wheel is damaged by inflow of foreign
materials.
Inspect both side of the turbocharger wheel after removing inlet and outlet pipe of the turbocharger. 1.
2.
3.
4.
5.
6.
7.
8.
9.

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1. SYSTEM DESCRIPTION OF E-VGT
(Electric-Variable Geometry Turbine)
The E-VGT turbocharger has one shaft where at each ends are installed with two turbines having
different angles to connect one end of housing to the intake manifold and the other end to the exhaust
manifold. As the turbine, at exhaust end, is rotated by exhaust gas pressure the impeller, at intake end,
gets rotated to send air around center of the impeller, being circumferentially accelerated by the
centrifugal force, into the diffuser. The air, which has been introduced to the diffuser having a passage
with big surface, transforms its speed energy into the pressure energy while being supplied to the
cylinder improving the volume efficiency. Also, the exhaust efficiency improves as the exhaust turbine
rotates. The turbocharger is often referred to as the exhaust turbine turbocharger.
1) Overview
Diffuser: With the meaning of spreading out it is a device that transforms fluid's speed energy into the
pressure energy by enlarging the fluid's passage to slow down the flow.
The E-VGT system installed to the D20DTR engine variably controls the passages of the turbine
housing to regulate the flow rate of the exhaust gas. The actuator of E-VGT is a DC motor actuator (E-
Actuator) which controls more quickly and precisely than the previous vacuum type actuator.
The engine ECU controls the E-Actuator electronically as follows:
At low speed: Narrows the flow passage for the exhaust gas, resulting in increasing the flow
speed of the exhaust gas and running the turbine quickly and powerfully.
At high speed: Expands the flow passage for the exhaust gas, resulting in increasing the mass
flow of the exhaust gas and running the turbine more powerfully. -
-

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E-VGT turbocharger
Improves engine power
2. COMPONENTS
Engine ECU (D20DTR)
E-VGT duty controlAccelerator pedal position
sensor
Transfers driver's will to
accelerate to ECU
Atmospheric pressure, RPM
signal
HFM sensor
Improves the engine powerCoolant temperature sensor
Operates the VGT according to
engine warm-upT-MAP sensor
Booster pressure and
temperature

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Control
rangeTurbocharger driving
mechanismControl method
EffectImproved
performance
At low
speedNarrows the flow
passage for the
exhaust gas by
folding the vanesThe flow rate is
increased as the
exhaust gas passes
the narrow passage
turbine & impeller
speed, Increased
compressive forceImproved
low speed torque
4. OPERATING PRINCIPLES
The E-VGT is designed to get more improved engine power in all ranges by controlling the turbine as
follows:
1) How it Works at Low Speed
Normal turbocharger cannot get the turbo effect because the amount of exhaust gas is not enough and
the flow speed is slow in a low speed zone, but VGT allows the flow passage of exhaust to narrow,
resulting in increasing the flow speed of exhaust gas and running the turbine quickly and powerfully.
Therefore, as VGT can intake more air than normal turbocharger, it can give the benefit of the increased
output even in a low speed zone.
Turbocharger lag
The turbocharger is at idle speed when there is no load or it is in the normal driving condition. During
this period, the amount of exhaust gas passing through the turbine is not enough to turn the
compressor wheel (impeller) fast. Therefore, the intake air is not compressed as needed.
Because of this, it takes time for turbocharger to supply the additional power after the accelerator
pedal is depressed. This is called "turbocharger lag". Basic principle at low speed
At low speed, it utilizes the principle of venturi.
For example, when air flows through the venturi
tube, the flow speed is faster and the pressure is
lower at the point "A". In this case, if the inner
diameter of venturi is more narrowed, the flow
speed is so much faster (refer to the equation).

2) How it Works at High Speed
In a high speed zone, the amount of exhaust gas increases and it is accompanied with a great force.
Therefore, if the inner diameter of venturi is more widened, the turbine in the turbocharger by the
releasing force of abundant exhaust gas can deliver a more increased energy to the compressor. The
output will increase in submission to the increase of intake air volume.
Control
rangeTurbocharger driving
mechanismControl
methodEffectImproved
performance
At high
speedExpands the
flow passage for
the exhaust gas
by unfolding the
vanesThe flow rate is
increased due to the
expanded
Increased turbine &
impeller speed,
Increased
compressive forceImproved
maximum
power

Differential pressure
sensor
Calculates the amount of
PM collected by reading the
pressure difference between
before and after the CDPF.Engine ECU
DCM 3.7
Post-injectionThrottle
valve
Regulates the rate of air
intake.
CDPF
DOC+DPFFront temperature
sensor
Protects the turbocharger.Rear temperature sensor
Measures the temperature
of fuel combustion.
2. COMPONENT
For details, refer to section "Engine Control". *

(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)E-VGT actuatorAccelerator pedal
module
Crankshaft
position sensorOxygen sensor
T-MAP sensor
Coolant
temperature
sensor
D20DTR ECU
Front EGT sensor