
Starting and Operating
Your Vehicle
Starting the Diesel Engine
Your diesel engine starts differently than a gasoline
engine.
Automatic Transmission
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine won’t start in any other position — that’s a
safety feature. To restart when you’re already moving,
use NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage
the transmission. Shift to PARK (P) only when your
vehicle is stopped.
Manual Transmission
(Pickup Models Only)
Move your shift lever to neutral and hold the clutch pedal
to the floor while starting the engine. Your vehicle won’t
start if the clutch pedal is not all the way down — that’s
a safety feature.
Starting Your Engine
1. Turn your ignition key to RUN.
Observe the wait to start light. SeeWait to Start
Light on page 3-7. This light may not come on if
the engine is hot.
2. As soon as the wait to start light goes off,
immediately turn the ignition key to START.
When the engine starts, let go of the key.
Your engine has a fast warm-up glow plug system.
The wait to start light will illuminate for a much
shorter time than most diesel engines, due to the
rapid heating of the glow plug system.
Notice:Holding your key in START for longer than
15 seconds at a time will cause your battery to be
drained much sooner. And the excessive heat can
damage your starter motor.
Notice:If the wait to start light stays on after
starting your vehicle, your vehicle may not run
properly. Have your vehicle serviced right away.
3. If the engine does not start after 15 seconds of
cranking, turn the ignition key to LOCK. Wait
one minute for the starter to cool, then try the
same steps again.
If you’re trying to start your engine after you’ve run
out of fuel, follow the steps inRunning Out of Fuel
on page 5-11.
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Be sure you are using the proper fuel for existing
weather conditions. SeeDiesel Fuel Requirements
and Fuel System on page 5-2.
If the engine starts, runs a short time, then stops, your
vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such as
ether, in the air intake. They could damage
your engine. There could also be a re, which
could cause serious personal injury.
Elevated Idle/Exhaust Restrictor
The engine has a cold temperature high idle and exhaust
restrictor feature which elevates the engines idle speed
from 680 to 1200 rpms, and restricts the exhaust gas
flow, when outside temperatures are below 32°F (0°C),
and the engine coolant temperature is below 150°F
(65°C.) This feature enhances heater performance
by raising the engine coolant temperature faster.For pickup models, this feature can be turned off and
on using the DIC steering wheel control buttons. If your
vehicle is not equipped with the DIC steering wheel
control buttons, do the following to turn on this feature:
1. Turn the ignition to RUN, with the vehicle off.
2. Press the accelerator pedal to the floor and hold
while quickly pressing the brake pedal three times
in less than eight seconds.
3. Release the accelerator pedal and start the engine.
When the engine is started, it will slowly ramp up to the
high idle speed after a delay of a few seconds up to
approximately two minutes. For this method to work
properly there must be no throttle or brake pedal faults.
The engine idle speed will return to normal once the
following conditions are met:•Once engine coolant temperature reaches
150°F (65°C).
•Air intake temperature reaches 32°F (0°C).
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Fuel Operated Heater (FOH)
(Van Models Only)
If your vehicle includes a fuel operated heater (FOH),
it will enhance heater performance and will reduce the
amount of time it takes to warm the inside of your vehicle
in cold conditions below 40°F (4.4°C). The fuel operated
heater is installed in the frame rail on the driver’s side of
the vehicle and uses diesel to warm up the engine
coolant, which finally warms up the passenger’s cabin
air. The FOH works automatically, depending on the
fuel level, engine coolant temperature and outside air
temperature. It works only with the engine running.
Engine Coolant Heater
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You’ll get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The cord is located in the engine compartment,
on the passenger’s side of the vehicle, near the
right side engine mount.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously injured.
Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord
will not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a computer which monitors operation
of the fuel, timing, and emission control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the life
of the vehicle, helping to produce a cleaner environment.The check engine light comes on to indicate when service
is required. Malfunctions often will be indicated by the
system before any problem is apparent. This may prevent
more serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after awhile, your emission controls may not
work as well, your fuel economy may not be as good,
and your engine may not run as smoothly. This could
lead to costly repairs that may not be covered by
your warranty.
Notice:Modi cations made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modi cations to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test. Pickup Models
Van Models
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Oil Pressure GageThe oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is running.
Canadian vehicles indicate pressure in kPa (kilopascals).
Oil pressure may vary under different driving conditions
and oil types. The DURAMAX
®engine may generate
oil pressure in excess of 80 psi (548 kPa) under certain
conditions, especially in cold temperatures. This is a
normal operating range.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil. United States
(Pickup Models)Canada
(Pickup Models)
United States
(Van Models)Canada
(Van Models)
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Diesel Fuel Requirements and
Fuel System
Some states and provinces have restrictions on the
purchase of diesel fuel for light-duty vehicles and require
you to buy permits or pay special taxes. Some of these
restrictions apply only to residents, and others apply
to both residents and visitors. These restrictions can
change. To learn the current restrictions in any state
or province, contact your auto club, the police or other
officials.
Diesel Engine Fuel
Notice:Diesel fuel or fuel additives not
recommended in this manual could damage your
fuel system, fuel-operated heater (FOH) (Van models
only) and engine. Your warranty would not cover
this damage. And:
Diesel fuel that has been mixed with engine oil
or automatic transmission uid could damage
your engine and emission controls.
Aftermarket diesel fuel additives are not tested
by General Motors. Some additives, particularly
those which contain alcohol or water emulsi ers,
may damage your fuel system. If you believe that
unique circumstances call for a fuel additive to
be used, consult your dealer for advice.
If you ever run out of diesel fuel, it can be difficult
to restart your engine. To avoid all this, never let
your tank get empty.
If gasoline is ever accidentally added to the fuel
tank, to avoid severe engine damage, do not run
the engine until the fuel tank can be drained.
If you run out of fuel,Running Out of Fuel on page 5-11
tells you how to restart your engine.
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If you have a pickup model and this happens, a WATER
IN FUEL message will appear on the Driver Information
Center (DIC). The water must be drained.
If you have a van model
and this happens, this
water in fuel warning
light will appear on the
instrument panel cluster.
The water must be drained from both chassis mounted
fuel filters. Your dealer can show you how to do this.Water in Fuel Light Chart
If the WATER IN FUEL DIC message or water in fuel
warning light comes on, use this chart.
Water In Fuel Light/Message Chart
Problem Recommended Action
Light/Message comes on
intermittently.Drain water from fuel
filter.
Light/Message stays on:
•At temperatures
above freezing.Drain fuel filter
immediately. If no water
can be drained and light
stays on, see your dealer
for assistance.
•At temperatures
below freezing.Drain fuel filter
immediately. If no water
can be drained — water
may be frozen in water
drain system. Water may
be frozen in the fuel lines.
Move the vehicle to a
warm location to thaw
out, and then drain filter
system.
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Water In Fuel Light/Message Chart
(cont’d)
Problem Recommended Action
•Immediately after
refueling, large
amount of water
possibly pumped
into fuel tank.Fuel tank purging
required. See your
dealer for assistance.
Notice:If you drive when this warning indicator is
on, you can damage your fuel injection system and
your engine. If the indicator comes on right after you
refuel, it means water was pumped into your fuel
tank. Turn off your engine immediately. Then, have
the water drained at once.
Hard starting, hesitation or flat performance at high speed
or during hard acceleration may be an indication of
premature fuel filter plugging due to dirty or contaminated
fuel. The filter element may need to be changed if this
happens. SeeFuel Filter Replacement on page 5-12.To drain water, do the following:
1. Stop and park the vehicle in a safe place.
Turn off the engine and apply the parking brake.
2. Remove the fuel cap.
3. Place a fuel-resistant container under the fuel
filter(s). For pickup models, the filter drain valve
is located in the engine compartment, on the
passenger’s side of the vehicle, on the bottom of the
fuel filter. For van models, the filter drain valves for
the primary and secondary fuel filters are located in
the chassis (inside frame rail) compartment. They
are on the driver’s side of the vehicle, below the
fuel filters.
4. For pickup models,
open the drain valve
by turning it two to
three turns. When fuel
empties from the valve,
all the water has been
drained. Close the
valve hand tight. To
help remove all the
water, press the priming
pump several times.
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