1998 GMC ENVOY engine

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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I A CAUTION:
Don’t keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil
as soon as possible and have your
vehicle serviced.
I
I NOTICE:
Damage to your engine from neglected oil
problems can be costly and
is not covered by
your warranty.
Security Warning Light
SECURITY
This light will come on
briefly when you turn the
key toward START. The
light will stay on until the
engine 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 dealer.
This light should also flash as you open
the door (if your
ignition is off).
This is a reminder to activate the
theft-deterrent system. See “Content Theft-Deterrent” in
the Index for more information.
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Service 4WD Light
SERVICE
4WD
This light should come on
briefly when you turn on the
ignition, as a check to show
you it is working.
The
SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage
to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
Check Gages Light
The CHECK GAGES light
CHECK
GAGES
will come on briefly when
you are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil pressure
gages
to see if they are in the warning zones.
Gate Ajar Light
GATE
AJAR
This light will come on
briefly when
you are
starting the engine.
If it stays on, your liftgate
is ajar. Try closing the liftgate
again. Never drive with the liftgate even partially open.
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Mode Knob - Automatic Operation
The right knob on the control panel allows you to
choose the direction of air delivery. When the system is
set for automatic operation, sensors will control the air
delivery mode.
Air will come primarily from the floor or
instrument panel outlets, with some air directed to the
windshield to prevent fogging.
When the system is in AUTO mode, the air conditioning
light will turn on, and the recirculation and outside air
lights turn
off. With the system in full auto control
(both the fan and mode knobs
in AUTO), you still have
the ability to override any function. However,
continually overriding the outside air or the
A/C
compressor will limit the ability of the system to cool
the vehicle quickly.
If you push a button for a function which is nor
available, the light next to that button will flash three
times to alert you that it’s not available.
To find your comfort zone, start with the
74°F (23 O C)
setting and allow about 20 minutes for the system to
adjust the temperature if necessary.
With the automatic setting, the
air conditioning compressor
automatically cycles when needed to cool the
air. In cold
weather, when the system senses the need for heat, the
airflow
will be directed out the floor outlets. As the interior temperature approaches the desired setting, the
blower speed will decrease. To maintain interior comfort,
the &ow will adjust between the instrument panel
air
outlets and floor outlets. On bright sunny days in cool
weather, the alrflow may come out
of the air conditioning
and floor outlets (bi-level mode) to maintain comfort and
prevent stuffiiess.
To avoid blowing cold
air in cold weather, the system will
delay turning on the fan until warm
air is available. The
length of delay depends on the outside
air temperature,
engine coolant temperature or the time since the engine was last started.
As the coolant warms up, the blower fan
speed will gradually increase and
air will flow from the
heater outlets, with some airflow to
the windshield to
prevent fogging under most normal conditions.
If your vehicle is sitting out on a warm day and you
have the fan set on AUTO, the air will first flow out of
the floor air outlets
for a few seconds. That is normal.
This is to expel hot air from the air outlets.
As the air is
cooled, the airflow will move through the
air
conditioning outlets.
Be careful not to put anything over the solar sensor
located around the center of the instrument panel.
This sensor is used by the automatic system to
regulate temperature.
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Air Conditioning
On hot days, open the windows long enough to let hot
inside air escape. This reduces the time
it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
Heating
For quick cool-down on very hot days, A/C should be
enabled with the temperature knob turned
to the left and
the OUTSIDE
AIR button should not be active. This
setting should be used to keep odors and/or dust from
entering the vehicle. For normal cooling on hot days,
use
A/C with the temperature knob turned to the left.
On cool but sunny days, use BI-LEVEL
A/C to deliver
warm air to the floor and cooler air to the instrument
panel outlets.
When the air conditioner is on, you may sometimes
notice slight changes
in your vehicle’s engine speed
and power.
This is normal because the system is
designed to cycle the compressor on and off to keep the
desired temperature. The heater
works best
if you keep your windows closed
while using it.
On cold days, use HEATER with the
temperature knob turned
to the right. BLEND is useful
in cool weather when
you have fog or ice on the
windshield
or side windows.
If you use the optional engine coolant heater before
starting your engine, your heating system will produce
warmer air faster to heat the passenger compartment in
cold weather. See “Engine Coolant Heater”
in the Index.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use PANEL with the OUTSIDE
AIR
button enabled to direct outside air through your vehicle.
Airflow is through the instrument panel outlets.
Your vehicle’s ventilation system supplies outside air to
the inside
of your vehicle when it is moving. When the
vehicle is not moving, you can get outside air to flow
through by selecting
any mode and any fan speed.
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Audio Systems
Your Delco Electronics audio system has been designed
to operate easily and give years
of listening pleasure.
You will get the most enjoyment out of it if you acquaint
yourself with
it first. Find out what your Delco
Electronics system can do and how to operate all its
controls, to be sure you’re getting the most
out of the
advanced engineering that went into it.
Setting the Clock
Press and hold HR until the correct hour appears on the
display. Press and hold
MN until the correct minute
appears
on the display. To display the clock with the
ignition
off, press RECALL or HR/MN and the time
will be displayed for
a few seconds. There is an initial
two-second delay before the clock goes into the
time-set mode.
AM-FM Stereo with Cassette Tape Player
Included with the AM-FM Stereo with Cassette Tape
Player are six
Base@ high performance speakers and a six
channel Bose amplifier. Please see your dealer for details.
Playing the Radio
PWR-VOL: Press this knob to turn the system on and
off.
To increase volume, turn the knob to the right. Turn
it to the left to decrease volume. The knob is capable of
being rotated continuously.
REAR DSPL: When the primary radio is turned on,
press
this button to turn the rear seat audio display on.
Press
it again to turn the rear seat audio display off.
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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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