1998 GMC SIERRA fuel cap

If the light stays on, or comes on when you’re driving,
your vehicle needs service.
If the regular brake system
warning light isn’t on, you still have brakes, but you
don’t have anti-lock brakes.
If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there‘s a problem
with your regular brakes. See
“Brake System Warning Light” earlier
in this section.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn‘t come on then. have it fixed
so it will be
ready to warn you
if there is a problem.
Engine Coolant Temperature Gage
1
This gage shows the engine
coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read
210°F (100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the
260°F (1 25 “C) mark. If the
gage reaches the
260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
The “Problems on
the Road,” section of this manual shows
what
to do. See “Engine Overheating” in the Index.
Malfunction Indicator Lamp (Service
Engine
Soon Light) (Gasoline Engine)
SERVICE
ENGINE
SOON
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission
control systems.
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Turn the key off, wait at least 10 seconds and restart the
engine.
If the light remains on steady, see “If the Light
Is On Steady” following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center
for service.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently
put fuel into your vehicle?
If
so, reinstall the fuel cap, making sure to fully install
the cap. The diagnostic system can determine if the fuel
cap has been left off or improperly installed.
A loose or
missing fuel cap will allow fuel to evaporate into the
atmosphere.
A few driving trips with the cap properly
installed should turn the light
off.
Did you just drive through a deep puddle of water‘?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out.
A few driving trips should turn the light off.
Are you low on fuel? As
your engine starts to run
out of fuel, your engine may
not run
as efficiently as designed since small amounts of
air are sucked into the fuel line causing
a misfire. The
system can detect this. Adding fuel should correct this
condition. Make sure to install the
fuel cap properly. It
will take
a few driving trips to turn the light off.
Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel (see
“Fuel”
in the Index). Poor fuel quality will cause your
engine not to run
as efficiently as designed. You may
notice this as stalling after start-up, st.alling
when you
put the vehicle into gear, misfiring, hesitation on
acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the light
to turn on.
If
you experience one or more of these conditions,
change the fuel brand
you use. It will require at least one
full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic
tools to fix any mechanical or electrical
problems that may have developed.
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Fuel Gage
The fuel gage, when the
ignition is on, tells you
about how much fuel you
have left
in your tank.
The
gage will first indicate EMPTY (E) before you
are out of fuel, and you should get more fuel as soon
as possible. Here
are four situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before the
gage reads FULL
(F).
It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may have
indicated the tank was half
full, but it actually took a
little more or less than half the tank’s capacity to
fill
the tank.
The gage moves a little when you turn a corner or
speed up.
The gage doesn’t go back to EMPTY (E) when you
turn off’ the ignition.
If you have a diesel engine, see “Fuel Gage” in the
Diesel Engine Supplement.
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Mode Knob
The right knob on the control panel allows you to
choose the direction
of air delivery. The control knob
can be placed in any position between two mode settings
to blend the flow of air.
+e
/$ VENT This setting directs air through the
instrument panel outlets.
+’ VENT/HEAT Use this setting to divide airflow
between the floor outlets and instrument panel outlets.
+’ HEATER: This setting directs air through the
+e
0
heater floor outlets.
+’ DEFOG: This setting directs air to the heater
we
outlets and toward the windshield.
DEFROST This setting directs air toward the
windshield.
Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the titne
it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best. The recirculation button, between the
fan and
temperature
knobs, allows the air inside your vehicle to
be recirculated. This setting helps to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also cools the air the fatest and
can be used
to keep unwanted odors and/or dust from
entering the vehicle. When using the air conditioner,
turn off recirculation after the vehicle reaches
a
comfortable interior temperature. When the right knob
on the control panel is between HEATER and
DEFROST, the recirculation feature will not function.
The A/C button, between the temperature and mode
knobs, allows the air coming into your vehicle to be
cooled. This setting is useful for normal cooling on hot
days. When you use
A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches
a comfortable interior temperature.
With the A/C
on, move the temperature knob to MAX
for maximum cooling. This setting also puts the system
in the recirculation mode and helps to maximize your air
conditioner‘s performance and your vehicle’s fuel
economy. This setting also cools the air the Fdstest. After
the vehicle‘s interior reaches
a comfortable temperature,
move the temperature knob to the right, to place the air
conditioning system
in the normal mode.
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Loading Your Vehicle
~EE ~NER'S MANUAL FOR ADDITIONAL INFORMATION. TI
The CertificatiodTire label is found on the rear edge of
the driver's door or in the Incomplete Vehicle Document
in the cab.
The label shows the size of your original tires and the
inflation pressures needed to obtain the gross weight
capacity
of your vehicle. This is called the Gross Vehicle
Weight Rating (GVWR). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The CertificatiodTire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR).
To find out the actual loads on
your front and rear axles, you need to
go to a weigh
station and weigh your vehicle. Your dealer can help
you with this. Be sure to spread out your load equally on
both sides
of the centerline.
Never exceed the GVWR
for your vehicle, or the
GAWR for either the front or rear axle.
And,
if you do have a heavy load, you should spread
it out.
A CAUTION:
In the case of a sudden stop or collision, things
carried in the bed of your truck could shift
forward and come into the passenger area,
injuring
you and others. If you put things in the
bed of your truck, you should make sure they are
properly secured.
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and
a part devoted to its appearance care.
6-2
6-3
6-5
6-6
6- 8
6-9
6- 13
6- 14
6-18
6-2
I
6-24
6- 25
6-26
6-26
6-28 6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries (Gasoline Engines)
Filling Your Tank (Gasoline Engine)
Filling a Portable Fuel Container
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engine)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat
, 6-33
6-3 3
6-35
6-39
6-39
6-50
6-5
1
6-6 1
6-62
6-65 6-69
6-70
6-70
' 6-76
6-77 6-79 Power
Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Electrical System Replacement
Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
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Filling Your Tank (Gasoline Engine)
If your vehicle has a diesel engine, see “Filling Your
Tank (Diesel Engine)” in
the Diesel Engine Supplement. On
a chassis-cab model, refuel the front tank first, or in
instances when only
a partial fuel fill is desired. An
automatic transfer mechanism
will maintain
approximately equal fuel levels
in both tanks, so no
switching is required by the operator.
Gasoline vapor is highly flammable. It burns
violently, and that can cause very bad injuries.
Don’t smoke if you’re near gasoline or refueling
your vehicle. Keep sparks, flames and smoking
materials away from gasoline.
The fuel cap is located on the left side of your vehicle.
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While refueling, let the cap hang by the tether below the
fuel filler neck.
To remove the cap, turn it slowly to the left
(counterclockwise).
If you get gasoline on yourself and then
something ignites it, you could be badly burnea.
Gasoline can spray out on you if you open the
fuel filler cap
too quickly. This spray can happen
if your tank is nearly full, and is more likely in
hot weather. Open the fuel filler cap slowly and
wait for any “hiss” noise to stop. Then unscrew
the cap
all the way.
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