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14-4
2. CAUTIONS
Standard pattern of soot accumulation ▶
(1) Abnormal Soot Accumulation (2) Normal Soot Combustion
Cautions to protect the catalyst filter ▶
Use the designated fuel only.
Observe the recommended service intervals of engine oil.
Check the engine oil level frequently and add if necessary.
Do not idle the vehicle unnecessarily.
Do not turn off the engine while the vehicle is running.
Do not shift the gear selector lever to neutral when going downhill.
Do not use improper engine oil or fuel additives.
Do not drive for a long time when the warning lamp is illuminated.
Make sure no flammable material, such as dry grass or tissue paper, contacts with the catalyst
filter while the vehicle is parked.
For the vehicles used in urban traffic, driving on the expressways for more than 1 hour at least
once per week is needed so that the PM inside CDPF isn't collected to one side only. -
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15-90000-00
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.
<00760097008c00990088009b00900095008e0047009b008c00940097008c00990088009b009c0099008c0047009900880095008e008c00470096008d0047006c006a007c00470090009a0047009500960099009400880093009300a000470054005b005700
47009b009600470052005f005c00b6006a004700880095008b> protected from factors like oil,
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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15-370000-00
HFM (intake air
temperature)Cooling fan module
DSI 6 A/T (ATF
temperature)Coolant
temperature senso
r
Refrigerant
pressure sensor
Relay box
(12) Cooling fan control
A. Overview of cooling fan and A/C compressor
The cooling system maintains the engine temperature at an efficient level during all engine
operating conditions. The water pump draws the coolant from the radiator. The coolant then
circulates through water jackets in the engine block, the intake manifold, and the cylinder head.
When the coolant reaches the operating temperature of the thermostat, the thermostat opens.
The coolant then goes back to the radiator where it cools. The heat from automatic transmission
is also cooled down through the radiator by circulating the oil through the oil pump. ECU controls
the electric cooling fans with three cooling fan relays to improve the engine torque and air
conditioning performance.
For detailed information, refer to Chapter "Air Conditioning System".
B. Components
A/C compressor
D20DTR ECU
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15-48
E. Cautions
Use only specified Engine Oil (approved by MB Sheet 229.51) for CDPF. -
Use only specified engine oil (Low Ash Oil) ▶
The vehicle equipped with CDPF should use specific engine oil to improve the engine
performance and fuel economy, and ensure the service life of CDPF. -
Issue with normal engine oil ▶
Sulfur, one of the contents of engine oil is burned and generates soot that is not regenerated
by the DPF. This remains on the filter as ashes and keeps accumulating. Eventually, this
ashes will block the filter. -
Benefit for specified engine oil ▶
Minimized the sulfur content of engine oil which reduces the service life.
Improved fuel economy and emission level of CO2 with high performance and low viscosity.
Increased service life of engine oil with high resistance to temperature. -
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Problems when using unspecified engine oil ▶
The service life of filter may be reduced by 30% or more by the ashes accumulated on the
filter.
The fuel economy may be reduced because of engine rolling resistance, frequent
regeneration of DPF. -
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These problems are also caused by oil with high sulfur content, such as tax exemption oil
and heating oil, etc. *
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01-31113-01
1. DESCRIPTION AND OPERATION
1) Cleanliness and Care
An automobile engine is a combination of many machined, honed, polished and lapped surfaces
with tolerances that are measured in the ten-thousanths of an inch.
When any internal engine parts are serviced, care and cleanliness are important.
A liberal coating of enigne oil should be applied to friction areas during assembly, to protect and
lubricate the surfaces on initial operation. Proper cleaning and protection of machined surfaces
and friction areas is part of the repair procedure.
This is considered standard shop practice even if not specifically stated.
Whenever valve train components are removed for service, they should be kept in order. They
should be installed in the same locations, and with the same mating surfaces, as when they were
removed.
Battery cables should be disconnected before any major work is performed on the engine. Failure
to disconnect cables may result in damage to wire harness or other electrical parts.
Page 358 of 828
01-8
Front View ▶
NO. FUNCTION NO. FUNCTION
1 HFM Sensor 12 Intake Manifold
2 Intake Air Duct 13 Cylinder Head
3 Cylinder Head Cover 14 Exhaust Manifold
4 Ignition Coi 15 Dipstick Guide Tube and Gauge
5 Spark Plug Connector 16 Connecting Rod
6 Fuel Distributor 17 Crankshaft
7 Injector 18 Engine Mounting Bracket
8 Exhaust Camshaft 19 Starter
9 Intake Camshaft 20 Crankcase
10 Valve Tappet 21 Oil Pump Sprocket
11 Intake Valve 22 Oil Pan
NO. FUNCTION NO. FUNCTION
23 Camshaft Adjuster 29 Oil Pump Drive Chain
24 Oil Filler Cap 30 Oil Strainer
25 Engine Hanger Bracket 31 Oil Pump
26 Cooling Fan and Viscous Clutch 32 Ring Gear and Flywheel of Drive Plate
27 Oil Filter 33 Piston
28 Timing Chain
Side View ▶
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01-91113-01
4. DIAGNOSTIC INFORMATION AND PROCEDURE
1) Oil Leak Diagnosis
Most fluid oil leaks are easily located and repaired by visually finding the leak and replacing or
repairing the necessary parts. On some occasions a fluid leak may be difficult to locate or repair.
The following procedures may help you in locating and repairing most leaks.
Finding the Leak ▶
Identify the fluid. Determine whether it is engine oil, automatic transmission fluid, power
steering fluid, etc.
Identify where the fluid is leaking from. -
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After running the vehicle at normal operating temperature, park the vehicle over a large
sheet of paper.
Wait a few minutes.
You should be able to find the approximate location of the leak by the drippings on the
paper. ·
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Visually check around the suspected component.
Check around all the gasket mating surfaces for leaks. A mirror is useful for finding leaks
in areas that are hard to reach.
If the leak still cannot be found, it may be necessary to clean the suspected area with a
degreaser, steam or spray solvent. -
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Clean the area well.
Dry the area.
Operate the vehicle for several miles at normal operating temperature and varying
speeds.
After operating the vehicle, visually check the suspected component.
If you still cannot locate the leak, try using the powder or black light and dye method. ·
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Clean the suspected area.
Apply an aerosol-type powder (such as foot powder) to the suspected area.
Operate the vehicle under normal operating conditoins.
Visually inspect the suspected component. You should be able to trace the leak path over
the white powder surface to the source. -
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- Powder Method ▶
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01-10
Black Light and Dye Method ▶
A dye and light kit is available for finding leaks, Refer to the manufacturer's directions when using
the kit.
Pour the specified amount of dye into the engine oil fill tube.
Operate the vehicle normal operating conditions as directed in the kit.
Direct the light toward the suspected area. The dyed fluid will appear as a yellow path
leading to the source. -
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Once the origin of the leak has been pinpointed and traced back to its source, the cause of the
leak must be determined in order for it to be repaired properly.
If a gasket is replaced, but the sealing flange is bent, the new gasket will not repair the leak. The
bent flange must be repaired also. Before attempting to repair a leak, check for the following
conditions and correct them as they may cause a leak.Repairing the Leak ▶
Gaskets ▶
The fluid level/pressure is too high.
The crankcase ventilation system is malfunctioning.
The seal bore is damaged (scratched, burred or nicked).
The seal is damaged or worn.
Improper installation is evident.
There are cracks in the components.
The shaft surface is scratched, nicked or damaged.
A loose or worn bearing is causing excess seal wear. -
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