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1. SPECIFICATION
Component Item Specification
Air cleaner elementFilter type Dry, filter element
Filter area
Service intervalEU: Change every 20,000 km (But, shorten the
service interval under severe conditions)
GEN: Change every 15,000 km (But, shorten the
service interval under severe conditions)
Air cleaner assemblyWeight 1.13 kg
Operating temperature
Capacity 6.5 L
IntercoolerCore material Aluminum
Size 510 x 110 x 70 (W x H x T)
Core size 510 x 110 x 63 (W x H x T)
Tank material Plastic (Molding)
Efficiency 80%
Shorten the service interval under severe conditions such as driving on a dusty road or off-road. *
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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.
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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.
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1719-02 Swirl control valve
Operates variably in accordance with the engine
load and rpm.
* For more information, refer to Chapter "Engine
Control".
1719-01 Intake manifold
Passage for intake air during the operation of
variable swirl valve
1719-16 Electric throttle body
* For more information, refer to Chapter "Engine
Control".
1. OVERVIEW
The intake system for D20DTF engine is equipped with an electric 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. To be sure to get the optimized swirl in intake manifold, the swirl valve and
dual type port have been adopted. And, the improved HFM sensor has been adopted to control the
intake air volume more precisely.
2. COMPONENTS
2330-01 Intercooler assembly
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2313-15 HFM (Hot Film Air-Mass) sensor
HFM sensor, version 6
* For more information, refer to Chapter "Engine
Control".
2313-01 Air cleaner assembly and
resonator
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3. INPUT/OUTPUT OF INTAKE SYSTEM
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4. OPERATING PROCESS
Work Flow
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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.