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message will display in the Electronic Vehicle Informa-
tion Center (EVIC) when service is required. Refer to
“Electronic Vehicle Information Center (EVIC)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion.
Do not remove the top of the air filter housing to
inspect the filter element on your diesel engine under
normal operating conditions.
The “SERVICE AIR FILTER” message could be displayed
periodically. This is because engine air flow requirements
change based on driving conditions. As the filter becomes
more restrictive and air flow requirements increase the
“SERVICE AIR FILTER” message will be displayed. The
message may not be displayed in subsequent drive cycles
if the same conditions are not met. The air filter element
should be replaced within 250 miles (402 km) from the
first time this message is displayed to ensure proper
engine operation during all driving conditions.CAUTION!
Driving with a restricted air filter can cause engine
damage. Driving in dusty environments for extended
periods will lead to rapid air filter plugging. Action
should be taken as soon as the “SERVICE AIR
FILTER” message is displayed.
If the vehicle experiences a sudden loss of engine power
while being driven in heavy snow or rain, or when
plowing snow, and/or the “SERVICE AIR FILTER” mes-
sage is displayed on the EVIC along with a chime that
repeats every 60 seconds, visually inspect the air filter for
snow/ice build up or extreme water saturation. If the air
filter is not damaged, remove all snow/ice and reinstall
air filter. If the air filter is damaged, replace filter element.
NOTE: The air filter housing contains a Mass Air Flow
sensor. This sensor is critical to proper engine operation
and component longevity. Any damage or modification
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MAINTAINING YOUR VEHICLE 103
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Priming If The Engine Has Run Out Of Fuel
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
1. Add a substantial amount of fuel to the tank, approxi-
mately 5 to 10 gal (19L to 38L).
2. Turn the ignition switch to the RUN position, wait for
four seconds, then turn the ignition switch back to the
OFF position. Repeat this step four times.
3. Start the engine using the “Normal Starting” proce-
dure. Refer to “Starting Procedures” in “Starting and
Operating” for further information.
CAUTION!
Do not engage the starter motor for more than 15 sec-
onds at a time. Allow two minutes between the
cranking intervals.
NOTE: The engine may run rough until the air is forced
from all the fuel lines.
WARNING!
Do not use alcohol or gasoline as a fuel blending
agent. They can be unstable under certain conditions
and be hazardous or explosive when mixed with
diesel fuel.
108 MAINTAINING YOUR VEHICLE
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•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
•Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance, poor gas
mileage, and increased emissions.
Charge Air Cooler – Inter-Cooler
The charge air cooler is positioned between the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50° to 100°F
(10° to 38°C). This cooling process enables more efficient
burning of fuel resulting in fewer emissions.To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
Brake System
Brake Master Cylinder – Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the “Brake System Warning Light” indicates
system failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” mark and an “MIN” mark. The fluid level must
be kept within these two marks. Do not add fluid above
the full mark because leakage may occur at the cap.
6
MAINTAINING YOUR VEHICLE 119
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Required Maintenance For Noise Control Systems
The following maintenance services must be performed
every six months or 7,500 miles (12 000 km) whichever
comes first, to assure proper operation of the noise
control systems. In addition, inspection and service
should be performed anytime a malfunction is observed
or suspected. Proper maintenance of the entire vehicle
will help the effectiveness of the noise control systems.Exhaust System
Inspect the entire exhaust system for leaks and damaged
parts. Devices such as hangers, clamps, and U-bolts
should be tight and in good condition. Damaged compo-
nents, burned or blown out mufflers, burned or rusted
out exhaust pipes should be replaced according to the
procedures and specifications outlined in the appropriate
service manual.
Air Cleaner Assembly
Inspect air cleaner housing for proper assembly and fit.
Make certain that the air cleaner is properly positioned
and that the cover is tight. Check all hoses leading to the
air cleaner for tightness. The air filter element must also
be clean and serviced according to the instructions out-
lined in the Maintenance Schedule section of this manual.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing
thereof: (1) the removal or rendering inoperative by any
126 MAINTAINING YOUR VEHICLE