1998 GMC SIERRA fuel

This system is called OBD I1 (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
SERVICE ENGINE SOON light
comes on to indicate that there is a problem and 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.
~OTICE:
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.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn’t come on, have it repaired.
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This light will also come on during a malfunction in one
of two ways:
0 Light Flashing -- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.
0 Light On Steady -- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
If the Light Is Flashing
The following may prevent’more serious aamage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
0 Avoiding steep uphill grades.
0 If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops flashing
and remains on steady, see “If
the Light Is On Steady” following.
If the light continues
to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
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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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Security Light
SECURITY
This light will come on
briefly when you turn the
key to
START.
The light will stay on until the engme starts. If the light
flashes, the Passlock@ System has entered a tamper
mode. If the vehicle fails
to start, see “Passlock” in
the Index.
If the light comes on continuously while driving and
stays
on, there may be a problem with the Passlock
System. Your vehicle will
not be protected by Passlock,
and you should see your
GM dealer.
Up Shift Light (If Equipped)
This light is used on
some models with
manual transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See ‘(Shift Light” or ;’Shift Speeds”
in this
section for more information.
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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
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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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steering, suspension, wheels, tires ana exhaust system
for damage.
Also, check the fuel lines and cooling
system for any leakage. Night driving is more dangerous than
day driving. One
reason is that some drivers are likely to
be impaired -- by
alcohol or
drugs, with night vision problems, or by fatigue.
Your vehicle will require more frequent service due to
off-road use. Refer
to the Maintenance Schedule for
additional information.
Driving at Night
Here are some tips on night driving.
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0
0
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Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror
to reauce me
glare from headlamps behind you.
Since you can’t see as well,
you may need to
slow down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light
up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off
the road in a safe place
and rest.
Night Vision
No one can see as well at night as in the daytime. But as
we get older
these differences increase. A 50-year-old
driver may require at least twice as much light
to see the
same thing at night as a 20-year-old.
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The exit speed is usually posted.
Reduce your speed according
to your speedometer, not
to your sense of motion. After driving for any distance
at higher speeds,
you may tend to think you are going
slower than you actually are.
Before Leaving on a Long Trip
Make sure you’re ready. Try to oe wed rested. If you
must start when you’re not fresh
-- such as after a day’s
work
-- don’t plan to make too many miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it’s ready to
go. If it needs
service, have
it done before starting out. Of course,
you’ll find experienced and able service experts in
GM
dealerships all across North America. They’ll be ready
and willing
to help if you need it.
Here are some things you can check before a trip:
0 Windshield Washer Fluid: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades: Are they in good shape?
0
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Fuel, Engine Oil, Other Fluids: Have you checked
all levels?
Lamps: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe,
trouble-free trip.
Is the tread good enough for
long-distance driving? Are the tires all inflated to the
recommended pressure?
Weather Forecasts: What’s the weather outlook
along your route? Should you delay your trip
a short
time
to avoid a major storm system?
Maps: Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as “highway hypnosis”?
Or is
it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There
is something about an easy stretch of road with the
same scenery, along with the hum of the tires on the road,
the drone of
the engine, and the rush of the wind against
the vehicle that can make you sleepy. Don’t let it happen to you! If it does, your vehicle can leave
the road in less
than n second, and you could crash and be injured.
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Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside.
CO could overcome you and kill
you.
You can’t see it or smell it, so you might not
know it is
in your vehicle. Clear away snow from
around the base
of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn’t collect there.
Open
a window just a little on the side of the
vehicle
that’s away from the wind. This will help
keep
CO out.
Run your engine only as long as you must. This saves
fuel. When you run
the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps
the
battery (or batteries) charged. You will need a
well-charged battery
(or batteries) to restart the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater run for a while.
If you have a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start the engine again and repeat this only
when you feel really uncomfortable from the cold. But
do it
as little as possible. Preserve the fuel as long as you
can.
To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour or
so until help comes.
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