Page 510 of 600

Do not allow the fluid and engine oil to make contact with the body paintwork and hoses.
If work on the fluid system such as fuel and oil, working area should be well ventilated and
smoking should be prohibited.
Gasket or seal on the fuel/lubrication system should be replaced with new ones and bolts and
nuts should be tightened as specified.
After removal/installation works, be sure to check whether there is leak on the connecting
section. -
-
-
-
If fine dust or foreign material enters into DI engine's fuel system, there can be serious
damages between HP pump and injectors. So, be sure to cover removed fuel system
components with cap and protect removed parts not to be contaminated with dirt. (Refer to
cleanness in this manual while working on DI engine fuel system)
When working on the fuel line between priming pump and injector (including return line),
always plug the openings with caps to prevent foreign materials or dust from entering to the
openings and connections.
The HP fuel supply pipe (HP pump to fuel rail) and HP fuel pipe (Fuel rail to injector) should
be replaced with new ones when removed. 1.
2.
3.
Electric devices should be handled more carefully.
Currently, the engine has a lot of electric devices. There could be poor engine performance,
incomplete combustion and other abnormal symptoms due to short circuit or poor contact.
Before work on engine and electrical equipment, be sure to disconnect battery negative (-)
terminal.
When replacing the electric device, use only genuine part and check the conditions of
connections and grounds. Loosened connection or ground makes cause a fire and personal
injury. -
-
Page 547 of 600

3) Post Injection and Air Mass Control
When the differential pressure sensor detects the pressure difference between the front and the
rear side of CDPF, the sensor sends signal indicating the soot is acumulated and the post
injection is performed to raise the temperature of exhaust gas. The amount of fuel injected is
determined according to the temperature of exhaust gas detected by the rear temperature sensor.
If the temperature is below
the amount of fuel injected is increased to raise the
temperature. If the temperature is over
the amount of fuel injected is decreased or not
controlled.
When the engine is running in low load range, the amount of post injection and the amount of
intake air are controlled. It is to raise the temperature by increasing the amount of fuel while
decreasing the amount of intake air.
2) Sytem Composition for Soot Combustion
When the engine is running in low load range, the temperature of exhaust gas is decreased as the
amount of fuel supplied is decreased. To burn the soot filtered in the CDPF, the control system
should be installed to check the operating range and increase the temperature of exhaust gas by
controlling the amount of fuel supplied and intake air.
Two temperature sensors and one differential pressure sensor monitor the CDPF's operating
range. According to these sensors' information, the throttle flap decreases the intake air entered
to the throttle body. Also, the fuel injection pattern is added to increase the temperature of
exhaust gas for soot combustion.
There are three fuel injection patterns (pilot injection, pre-injection and main injection). As the
CDPF is installed, the post injection pattern is added.
Page 552 of 600

1725-12
If the CDPF cannot reach the regeneration
temperature due to low speed driving or other
reason during the regeneration process, the soot
is continuously accumulated in the CDPF. When
this condition continues and the CDPF is
overloaded with soot, the engine warning lamp
blinks to inform this situation to the driver.
In order to solve this problem, drive the vehicle at
a speed of approx. 80 km/h for 15 to 20 minutes
to perform the CDPF regeneration process.
If the engine warning lamp on the instrument
cluster blinks, the CDPF is overloaded. In this
case, perform the step 2. 1.
2.
3.
If the vehicle is driven at a speed of 5 to 10 km/h
for an extended period of time, the soot
accumulated in the CDPF cannot be burnt as the
CDPF cannot reach the regeneration temperature.
Then, an excessive amount of soot can be
accumulated in the CDPF.
This case is much worse than the simple overload
of the CDPF. To inform this to the driver, the
engine warning lamp comes on and the engine
power is decreased to protect the system.
To solve this problem, blow soot between the
engine and exhaust system several times and
erase the related DTC. Then, check if the same
DTC is regenerated again. If so, check the DTC
related to the differential pressure sensor. 1.
2.
3.
Actually, the DTC for the CDPF is generated more often by the component related to the CDP
F
system, such as the differential pressure sensor, than by excessive soot in the CDPF.
Illuminating
Blinking
Page 592 of 600

3) Guidelines on Engine Service
To prevent personal injuries and vehicle damages that can be caused by mistakes during engine
and unit inspection/repair and to secure optimum engine performance and safety after service
works, basic cautions and service work guidelines that can be easily forgotten during engine
service works are described in.
Cautions before service works
For safe and correct works, you must observe the working procedures and instructions in this
manual. And, use the designated tools as follow:
Engine stand / Heavy duty engine jack
To prevent the engine from starting abruptly, do not allow anybody to get in the vehicle while
servicing in engine compartment.
Before work on engine and electrical equipment, be sure to disconnect battery negative (-)
terminal.
Before service works, be sure to prepare the works by cleaning and aligning work areas.
Do not allow the foreign material get into the fuel injection system.
When removing the engine, use only the safety hook on engine and engine hanger. Do not
support the bottom of oil pan with a jack. -
-
-
-
-
Completely drain the engine oil, coolant and fuel from engine before removal.
Before disassembling/assembling the engine components, carefully read the working
procedures in this manual.
Make sure to keep the specified tightening torques during installation.
Clean and properly lubricate the parts before reassembly.
Carefully check that there is not any interference while servicing. -
-
-
-
-
Page 593 of 600

0000-00
Do not allow the fluid and engine oil to make contact with the body paintwork and hoses.
If work on the fluid system such as fuel and oil, working area should be well ventilated and
smoking should be prohibited.
Gasket or seal on the fuel/lubrication system should be replaced with new ones and bolts and
nuts should be tightened as specified.
After removal/installation works, be sure to check whether there is leak on the connecting
section. -
-
-
-
If fine dust or foreign material enters into DI engine's fuel system, there can be serious
damages between HP pump and injectors. So, be sure to cover removed fuel system
components with cap and protect removed parts not to be contaminated with dirt. (Refer to
cleanness in this manual while working on DI engine fuel system)
When working on the fuel line between priming pump and injector (including return line),
always plug the openings with caps to prevent foreign materials or dust from entering to the
openings and connections.
The HP fuel supply pipe (HP pump to fuel rail) and HP fuel pipe (Fuel rail to injector) should
be replaced with new ones when removed. 1.
2.
3.
Electric devices should be handled more carefully.
Currently, the engine has a lot of electric devices. There could be poor engine performance,
incomplete combustion and other abnormal symptoms due to short circuit or poor contact.
Before work on engine and electrical equipment, be sure to disconnect battery negative (-)
terminal.
When replacing the electric device, use only genuine part and check the conditions of
connections and grounds. Loosened connection or ground makes cause a fire and personal
injury. -
-