1999 GMC C-SERIES fuel

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For example,
these symbols
are used on an
original battery:
CAUTION
POSSIBLE
INJURY
PROTECT
EYES BY
SHIELDING
CAUSTIC
BATTERY
ACID COULD
CAUSE
BURNS
AVOID
SPARKS OR
FLAMES
SPARK OR
FLAME
COULD
EXPLODE
BATTERY
These symbols
are important
for you and
your passengers
whenever your
vehicle is
driven:
DOOR LOCK
UNLOCK
FASTEN
SEAT
BELTS
POWER
WINDOW
AIR BAG
These symbols
have to do with
your lamps:
MASTER
LIGHTING
SWITCH
TURN
SIGNALS
PARKING
LAMPS
HAZARD
WARNING
FLASHER
DAYTIME
RUNNING
LAMPS
FOG LAMPS
These symbols
are on some of
your controls:
WINDSHIELD
WIPER
WINDSHIELD
WASHER
WINDSHIELD
DEFROSTER
REAR
WINDOW
DEFOGGER
VENTILATING
FAN
These symbols
are used on
warning and
indicator lights:
ENGINE
COOLANT
TEMP
BATTERY
CHARGING
SYSTEM
BRAKE
COOLANT
ENGINE OIL
PRESSURE
ANTI-LOCK
BRAKES
Here are some
other symbols
you may see:
FUSE
LIGHTER
HORN
SPEAKER
FUEL
Vehicle Symbols
These are some of the symbols you may find on your vehicle.
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NOTICE:
Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer. If you don't,
your engine might not perform properly.
If you ever have to have your vehicle towed, see
the part of this manual that tells how to do it
without damaging your vehicle. See ªTowing
Your Vehicleº in the Index.
Gasoline Engine Warm-Up
When you've started your engine, let it run for 20 or
30 seconds to warm up before you put a load on
the engine.
Drive at moderate speeds for the first few miles,
especially in cold weather. Running a cold engine at
high speed can damage it.
Restarting the Gasoline Engine While
Moving (Automatic Transmission)
If you have to restart the engine while the vehicle is
moving, you'll first have to shift the automatic
transmission to NEUTRAL (N). This safety feature
prevents starting the engine when the transmission is in
a drive gear.
Stopping the Gasoline Engine
Let your engine idle for a few seconds before turning it
off after you have finished driving your vehicle.
If you shift to NEUTRAL (N), set the parking brake.
If you shift to PARK (P), the auto
-apply feature will set
the parking brake.
If your vehicle has a two
-speed axle, put the range
selector in LOW. To be sure the axle has shifted into
LOW, engage the clutch and transmission the vehicle
may move slightly when you do this.
While your engine is idling before you turn it off, you
can make a list of any operational or handling concerns
to give to responsible maintenance personnel so they can
handle them right away.
Moisture will condense in a fuel tank that is almost
empty if the vehicle is not run for a while, even just
overnight under some conditions. So, it's always best to
refuel your vehicle at the end of each run.
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2-15
Engine Coolant Heater (If Equipped)
If your vehicle has this
feature, the plug
-in
receptacle is located behind
the front bumper as shown,
or in the component box
on the driver's side of
the vehicle.
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. Find the plug
-in receptacle (either behind the front
bumper or in the component box).
3. Plug a heavy
-duty, three-prong extension cord
(rated for at least 15 amps) into the vehicle's plug
-in
receptacle first. Then plug the extension cord 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 fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. Use a heavy-duty three-prong
extension cord rated for at least 15 amps.
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4. Before starting the engine, be sure to unplug the cord.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature.
Above 32
F (0
C), the coolant heater is not required.
From 32
F to
-10
F (0
C to -23
C), keep the
coolant heater plugged in at least two hours. Below
-10
F (-23
C), keep the coolant heater plugged in for
a minimum of eight hours or overnight. It will not harm
either the coolant heater or the vehicle to leave the
coolant heater plugged in longer than the times stated.
Be sure to remove and store the cord before starting the
engine. See ªDiesel Fuel Requirements and Fuel
Systemº in the Index for information on what fuel to use
in cold weather.
Diesel Engine Exhaust Brake
The exhaust brake is available on vehicles equipped
with a diesel engine and air brakes (or an air
compressor). It is located in the exhaust system.
The switch is on the upper
right side of the instrument
panel and turns the exhaust
brake on and off.
The exhaust brake indicator light is on when the exhaust
brake is in use.
The exhaust brake is used to help slow the vehicle and
may assist the vehicle's foundation brakes. The use of the
exhaust brake will assist the braking of the vehicle and
prolong the life of the foundation brake lining material.
When using the exhaust brake, the proper gear range
selection is important. The exhaust brake will be most
effective if the gear range selected is the lowest possible
range that does not allow the engine rpm to go more than
200 rpm above rated (full load) rpm as shown on the
Engine Information Plate. (Do not exceed 2900 rpm.)
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When the handle is pulled out, the engine air intake
supply is closed off from the front scoop and an under
hood air supply is opened. This control is intended only
for use in cold weather (32
F (0
C) or below) where
snow and ice might plug the external intake.
At temperatures above 32
F (0
C), keep the control
handle pushed in.
NOTICE:
Operating this vehicle with the engine air control
on when outside temperatures are above 32
F
(0
C), could lead to costly repairs not covered by
your warranty. It will also degrade fuel economy
and the engine will not run smoothly.
Exterior Lamps
Headlamps
The lamp switches are on the left side of your
instrument panel.
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Instrument Panel Cluster
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You'll know how fast
you're going, about how much fuel is left and many other things you'll need to drive safely and economically.
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2-65
This light should come on when the ignition is on, but
the engine is not running, as a check to show you it is
working. If it does not come on at all, have it repaired.
NOTICE:
If you keep driving your vehicle with this light
on, after a while, 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.
Engine Oil Pressure Gage
Gasoline Engine Diesel Engine
The engine oil pressure gage, on the lower right portion
of your instrument cluster, shows engine oil pressure
in psi (pounds per square inch) or in kPa (kilopascals).
Oil pressure may vary with outside temperature and oil
viscosity, but readings of 30 to 40 psi (205 to 275 kPa)
on gasoline engines at operating temperature and
moderate road speeds are normal. If you have a diesel
engine, the normal operating range should be between
35 and 70 psi (240 to 480 kPa).
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2-68 Fuel Gage
Gasoline Engine Diesel Engine
Your fuel gage will be on the right side of your
instrument cluster if your vehicle doesn't have the
optional tachometer. If you have a tachometer, your
fuel gage is on the lower left portion of your
instrument cluster.When the ignition is on, your fuel gage lets you know
about how much fuel you have left. When the gage first
shows empty, you'll still have a little fuel left, but you
should get more fuel soon.
If your vehicle has dual fuel tanks, the reading on the
gage is the average of the two tanks.
Here are four concerns of some operators. None of these
shows a problem with your fuel gage:

The gage moves a little when you turn a corner or
speed up.

The gage doesn't go back to empty when you turn
off the ignition.

At the gas station, the pump shuts off before the gage
reads full.

It takes a little more or less fuel to fill up than the
gage indicated.
If you have a diesel engine, also see your Caterpillar

Operation & Maintenance Manual.
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