1998 GMC ENVOY fuel

Malfunction Indicator Lamp
(Service Engine Soon Light)
SERVICE
ENGINE
SOON
United States Canada
Your
vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.
This system
is called OBD I1 (On-Board
Diagnostics-Second Gene.ration) 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.
a
a
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.
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.
This light will also come on during
a malfunction in one
of two ways:
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.
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.
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If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
Avoiding steep uphill grades.
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.
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.
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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, stalling when you
put the vehicle into gar, 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.
Engine Oil Pressure Gage
The 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 with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low
oil level or other problems causing low
oil pressure.
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Fuel Gage
@ FUEL ONLY
When the ignition is on,
the fuel gage tells you
about how much fuel you
have remaining.
Here are four things that some
owners ask about. None
of these
show a problem with your fuel gage:
0 At the gas station, the gas pump shuts off before the
u gage reads FULL (F).
0 It takes a little more or less fuel to fill up than the
gage indicated. For example, the gage
may have
indicated the tank
was half full, but it ~t~ally 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
The gage doesn’t go back to EMPTY (E) when you
speed up.
turn off the ignition.
Low Fuel Light
This light comes on when
the fuel tank
is low on fuel.
LOW
FUEL
TO turn it off, add fuel to the fuel tank. See “Fuel” in
the Index.
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Off-Road Driving with Your GM
Four-Wheel-Drive Vehicle
Also, see "Anti-Lock Brakes" in the Index.
Off-road driving can be great fun. But
it does have some
definite hazards. The greatest of these is the
terrain itself.
"Off-roading" means you've left the great North
American road system behind. Traffic lanes aren't
marked. Curves aren't banked. There are no road signs.
Surfaces can be slippery, rough,
uphill or downhill. In
short, you've gone right back to nature.
Off-road driving involves some new skills. And that's
why it's very important that
you read this guide. You'll
find many driving tips and suggestions. These will help
make
your off-road driving safer and more enjoyable.
Before You Go Off-Roading
There are some things to do before you go out. For
example, be sure to have all necessary maintenance and
service work done. Check to make sure all underbody
shields
(if so equipped) are properly attached. Be sure
you read all the information about your
four-wheel-drive vehicle
in this manual. Is there enough
fuel? Is the spare tire fully inflated'? Are the fluid levels
up where they should be? What are the local
laws that
apply to off-roading where you'll be driving?
If you
don't know, you should check with
law enforcement
people
in the area. Will you be on someone's private
land'?
If so. be sure to get the necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about
how to load your vehicle.
0 The heaviest things should be on the load floor and
forward of
your rear axle. Put heavier items as far
forward as you can.
Be sure the load is secured properly, so driving on
the off-road terrain doesn't toss things around.
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Driving in Water
Light rain causes no special off-road driving problems.
But heavy rain can mean flash flooding, and
flood
waters demand extreme caution.
Find
out how deep the water is before you drive through
it. If' it's deep enough to cover your wheel hubs. axles or
exhaust pipe, don't try it -- you probably won't get
through.
Also, water that deep can damage your axle
and other vehicle parts.
If the water isn't too deep, then drive through it slowly.
At fast speeds, water splashes on your ignition system
and your vehicle can stall. Stalling
can also occur if you
get your tailpipe under water. And, as long as your
tailpipe
is under water? you'll never be able to start your
engine. When you go through water. remember that
when your brakes get wet,
it may take you longer
to stop.
' Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and
you and your passengers could drown. If it's
only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Don't drive through rushing water.
See "Driving Through Wdter" in the Index for more
information
on driving through water.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can
be a fire hazard.
After operation
in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust system
for
da1nage. Also, check the fuel lines and cooling
system for any leakage.
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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 be well 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
0
0
0
0
0
0
WincJsl~ield Wcrshc~r- Fluid: Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blcrdes: Are they in good shape?
Fuel, Elzgirze Oil, Other Flr.ds: Have you checked
all levels‘?
Lcunps: 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 drivingi? Are the tires all inflated
to the
recommended pressure?
Wecrther Forec*cr.sts: What’s the weather outlook
along your route? Should
you delay your trip a short
time to avoid
a major storm system?
A4crp.s: Do you have up-to-date maps?
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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 charged.
YOLI will need a well-charged battery to
restart the vehicle, and possibly for signaling later
on
with your headlamps. Let the heater run for a while.
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.
Recreational Vehicle Towing
Vehicles with the electronic shift transfer case require
special modifications before they can be towed
in this
manner. Please contact your dealer
.for the towing
information that is appropriate
for yoc~r
particular vehicle.
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