1998 GMC ENVOY check engine

To help avoid hearing loss or damage:
0 Adjust the volume control to the lowest setting.
Increase volume slowly until you hear comfortably
and clearly,
NOTICE:
Before you add any sound equipment to your
vehicle
-- like a tape player, CB radio, mobile
telephone or two-way radio
-- be sure you can
add what
you want. If you can, it’s very
important to do it properly. Added sound
equipment may interfere with the operation
of
your vehicle’s engine, Delco Electronics radio or
other systems, and even damage them. Your
vehicle’s systems may interfere with the
operation
of sound equipment that has been
added improperly.
So, before adding sound equipment, check with
your dealer and be sure
to check Federal rules
covering mobile radio and telephone units.
Care of Your Cassette Tape Player
A tape player that is not cleaned regularly can cause
reduced sound quality, ruined cassettes or
a damaged
mechanism. Cassette tapes should be stored
in their
cases away from contaminants, direct sunlight and
extreme heat.
If they aren’t, they may not operate
properly or may cause failure of the tape player.
Your tape player should be cleaned regularly after every
SO hours of use. Your radio may display CLN to indicate
that you have used your tape player for
50 hours without
resetting the tape clean timer. If this message appears on
the display,
your cassette tape player needs to be
cleaned.
It will still play tapes, but you should clean it as
soon
as possible to prevent damage to your tapes and
player.
If you notice a reduction in sound quality, try a
known good cassette to see
if it is the tape or the tape
player at fault,
If this other cassette has no improvement
in sound quality, clean the tape player.
The recommended cleaning method for your cassette
tape player is the use
of a scrubbing action,
non-abrasive cleaning cassette with pads which scrub
the tape head
as the hubs of the cleaner cassette turn.
The recommended cleaning cassette is available through
your dealership
(GM Part No. 12344789).
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And, of course, actual stopping distances vary greatly
with the surface of the road (whether it‘s pavement or
gravel);
the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of the
vehicle and the amount of brake force applied.
Avoid needless heavy braking. Some people drive
in
spurts -- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic. This is a
mistake. Your brakes may not have time to cool between
hard stops. Your brakes will wear out rnucit faster
if you
do a lot of heavy braking.
If you keep pace with the
traffic and allow realistic following distances, you
will
eliminate a lot of unnecessary braking. Th, ti t means
better braking and longer brake life.
If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes.
If you do, the
pedal may get harder
to push down. If your engine
stops,
you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used
up, it may take longer to stop and the brake pedal
will be harder
to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is an
advanced electronic braking system that will help
prevent
;1 braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system
will check itself. You may
hear
a momentary motor or clicking noise while this test
is going on. This is normal.
If there’s a problem with the
anti-lock brake system, this
warning light
will stay on.
See “Anti-Lock Brake
System Warning Light”
in
the Index.
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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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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 CI second, and you could crash and
be injured
.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and to
the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest. service
or parking area and take
a nap, get some exercise, or
both. For safety, treat drowsiness on
the highway as
an emergency.
aLL - - ountain Roads
Driving on steep hills or mountains is different from
driving
in flat or rolling terrain.
If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips that can make
your trips safer
and more elljoyable. (See ”Off-Road
Driving“
in the Index for information about driving
off-road.)
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Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system and
transmission. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine
do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
‘ A CAUTION:
If you don’t shift down, your I brakes could get so
hot that they wouldn’t work well. You would then
have poor braking or even none going down a
hill. You could crash. Shift down to let your
engine assist your brakes on a steep
downhill slope. 0
0
/I CAC rION:
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do all the work of slowing down. They could get
so hot that they wouldn’t work well. You would
then have poor braking or even none going down
a hill. You could crash. Always have your engine
running and your vehicle in gear when you
go downhill.
0
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your
engine and transmission,
and you can climb the
hill better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Don’t swing wide or cut
across the center
of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could
be something in your lane, like a stalled car or
an accident.
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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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Driving with a Trailer
A CAUTION: I
0
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If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can’t see
or smell
CO. It can cause unconsciousness or
death. (See ‘(Engine Exhaust” in the Index.) To
maximize your safety when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle.
Do not use
RECIRCULATION because it only
recirculates the air inside your vehicle. (See
“Comfort Controls” in the Index.)
Towing a trailer requires a certain amount of experience, ~
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
arc
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you
start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to
be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you 1
would when driving your vehicle without a trailer. This
can help you avoid situations that require heavy braking
and sudden turns.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
0 Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s
a good idea to review these
sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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