SSANGYONG REXTON 2004.04, Manual

Page: 171 / 918

01-23
VEHICLE GENERAL
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3) DI Engine and Its Expected Problems and Remedies Can be
Caused by Water in Fuel
(1) SYSTEM SUPPLEMENT AGAINST PARAFFIN SEPARATION.
In case of Diesel fuel, paraffin, one of the elements, can be separated from fuel during winter
and then can stick on the fuel filter blocking fuel flow and causing difficult starting finally. Oil
companies supply summer fuel and winter fuel by differentiating mixing ratio of kerosene and
other elements by region and season. However, above phenomenon can be happened if
stations have poor facilities or sell improper fuel for the season.
In case of DI engine, purity of fuel is very important factor to keep internal preciseness of HP
pump and injector.
Accordingly, more dense mesh than conventional fuel filter is used. To prevent fuel filter internal
clogging due to paraffin separation, SYMC is using fuel line that high pressure and temperature
fuel injected by injector returns through fuel filter to have an effect of built-in heater (see fuel
system).
(2) SYSTEM SUPPLEMENT AND REMEDY AGAINST WATER IN FUEL
As mentioned above, some gas stations supply
fuel with excessive than specified water. In the
conventional IDI engine, excessive water in the
fuel only causes dropping engine power or
engine hunting. However, fuel system in the DI
engine consists of precise components so
water in
the fuel can cause malfunctions of HP pump
due to poor lubrication of pump caused by poor
coating film during high speed pumping and
bacterization (under long period parking).
To prevent problems can be caused by
excessive water in fuel, water separator is
installed inside of fuel filter. When fuel is
passing filter, water that has relatively bigger
specific gravity is accumulated on the bottom of
the filter due to centrifugal separation effect.
If water in the separator on the fuel filter exceeds a certain level, it will be supplied to HP pump
with fuel, so the engine ECU turns on warning light ( ) on the meter cluster and buzzer if
water level is higher than a certain level.
Due to engine layout, a customer cannot easily drain water from fuel filter directly, so if a
customer checks in to change engine oil, be sure to perform water drain from fuel filter. (See
fuel system for details.)