2003 FORD SUPER DUTY low oil pressure

DIESEL ENGINE INFORMATION
The Diesel engine fuel system consists of:
•a frame-mounted electric fuel supply pump
•an engine mounted fuel filter/water separator
•a fuel restriction sensor
•a unit injector for each cylinder
The combination fuel filter/water separator removes both water and
impurities from the fuel. The filter should be changed at the
recommended service interval. Refer to the scheduled maintenance guide
for more information. The filter bowl should be drained at regular
intervals or when the WATER IN FUEL light illuminates in the
instrument cluster.
The fuel injectors are located in the center of the combustion chambers
in the cylinder head between the rocker arm assemblies. The glow plug
system and fuel injection system are controlled through the Powertrain
Control Module (PCM).
Fuel is drawn from the fuel tank by a frame-mounted electric fuel pump.
The fuel pump provides pressurized fuel to the engine and is
electronically controlled by the fuel pump PCM relay. The fuel pump
contains a pressure relief valve for overpressure protection in the event
of restricted flow.
Lubrication system
It is important to change the engine oil at the recommended service
intervals, because oil viscosity is important in maintaining the oil
pressure required to actuate the fuel injectors. Extended oil change
intervals can negatively affect engine performance and fuel economy.
Pressurized oil from the turbocharger is also used to actuate an exhaust
backpressure warm-up system (if equipped). Pressurized oil from the
turbocharger is routed to the exhaust backpressure actuator. During
exhaust backpressure operation, the engine’s sound will be altered and
you may notice a change in engine performance while it’s engaged. This
function occurs only during cold weather warm-up cycle.
Fast start glow plug system
The glow plug system consists of:
•eight glow plugs
•the glow plug relay
Diesel information
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•engine oil temperature (EOT) sensor
•barometric pressure (BARO) sensor
The glow plug system is electronically controlled by the PCM. The PCM
energizes the glow plugs immediately after the ignition is placed in the
ON position, then determines how long the glow plugs will be on
according to the EOT and BARO sensors. The required time for the glow
plugs to be energized decreases as the engine oil temperature and
barometric pressure increase.
Engine cooling system
The cooling system contains an engine oil cooler which is mounted to
the side of the cylinder block. The cooler’s function is to regulate engine
oil temperature.
Engine governed speed
The engine governor is controlled by the PCM. The PCM controls fuel
input to limit maximum engine speed. It will not, however, prevent
engine overspeeding resulting from downshifting at high vehicle speed or
by descending steep grades at too high a vehicle speed for the selected
transmission gear.
For maximum vehicle speed in various gears, refer toManual
transmission shift speedsin theDriving tipschapter. Do not exceed
3,600 rpm. Maximum engine governed speed is 3,000–4,000 rpm
depending on engine load. Excessive rpm can only be achieved by
manually downshifting at too high of a vehicle speed.
Operating the engine beyond the governed speed can cause severe
engine damage.
Air filter restriction gauge, E-Series
The restriction gauge, located on
the clean-air side of the air cleaner
upper housing, shows if the air filter
is clogged. Refer toEngine
CompartmentinService points
chapter.
AIRFILTERGAUGECHANGEFILTERCHANGEFILTER
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4. When the engine starts, release the key. The glow plugs will continue
to be activated for up to two minutes. If the engine is not started before
the activation ceases, the glow plug system must be reset by turning the
ignition key to OFF.
5. After the engine starts, allow it to idle for about 15 seconds. (Do not
increase engine speed until the oil pressure gauge indicates normal
pressure.)
STOPPING THE ENGINE
Turn the ignition to OFF. To prolong engine life (after extended high
speed or maximum GVW operation), it is recommended that a hot engine
be allowed to operate at low idle for about 7–10 minutes which would
allow sufficient time for the turbocharged engine to cool down.
COLD WEATHER OPERATION
Changing to a lighter grade engine oil also makes starting easier under
these conditions. Refer toEngine Oil Specificationsin theGeneral
maintenance informationchapter.
At temperatures below–7°C (20°F), Number 2–D Diesel fuel may
thicken enough to clog the fuel filter. Your engine is equipped with a fuel
filter/heater/water/separator to keep the wax melted which will help
prevent fuel filter clogging. However, if the engine starts but stalls after a
short time and will not restart, the fuel filter may be clogged. For best
results in cold weather, use Number 1–D Diesel fuel or“winterized”
Number 2–D Diesel fuel which has an additive to minimize wax
formation.
Your vehicle is also equipped with a bypass relief valve, located on the
in-tank fuel sending unit, which provides fuel flow to the engine if the
fuel pickup should become plugged by ice or wax. To allow this bypass
valve to function and avoid engine fuel starvation, it is recommended
that, during cold weather operation 0°C (32°F) or below, the fuel level in
your tank should not be allowed to drop below 1/4 full. This will help
prevent air from entering the fuel system and stalling the engine.
In cold weather below 0°C (32°F) your Diesel engine will slowly increase
to a higher idle speed if left idling in P (Park). The sound of the engine
may change also, as an exhaust device engages to improve heater
performance and reduce exhaust smoke.
Starting
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