coolant temperature GMC ENVOY 1998 Owners Manual

To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver’s side of the engine
compartment, behind the underhood fuse block.
3. Plug it into a normal, grounded 110-volt AC outlet.
% CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind
of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into
a properly grounded three-prong
110-volt
AC outlet. If the cord won’t reach, use a
heavy-duty three-prong extension cord rated for
at least
15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away from
moving engine parts. If you don’t, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind
of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you’ll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
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Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay
on
for several seconds.
That’s normal.
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
This gage shows the engine
coolant temperature. If the
gage pointer moves into
the
red area, your engine is
too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions,
you should pull off the road, stop your
vehicle and turn off
the engine as soon as possible.
The “Problems on the Road” section
of this manual
shows you what to do. See “Engine Overheating”
in
the Index.
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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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Driving On Grades
Reduce speed and shift to a 1owe.r gear Iwfow you start
down a long or steep downgrade.
If you don’t shift
down. you might have to use your brakes
so much that
they would get hot and no longer work well.
On
a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating.
You should use DRIVE
(D) when towing a trailer.
Operating your vehicle
in DRIVE (D) when towing a
trailer
will minimize heat buildup and extend the life of
your transmission.
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a lower
temperature than at normal altitudes.
If you twn your
engine off imnlediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating.
To avoid this, let the engine run while
parked (preferably on level ground)
with the automatic
transmission
in PARK (PI for a few minutes before turning
the engine off.
If you do get the overheat warning. see
”Engine Overheating”
in the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached.
on a hill. If‘ something goes wrong, your rig
could start
to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here‘s
how
to do it:
1.
-. 3
3.
4.
5.
Apply your regular brakes, but don’t shift into
PARK
(P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes
until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking
brake, and then shift into PARK
(P).
Release the regular brakes.
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Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See "Gages" in the Index.
If Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you
badly, even if you ,just open the hood. Stay
away
from the engine if you see or hear steam coming
from
it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is
cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged.
The costly repairs would not be
covered
by your warranty.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change
it. See
”Scheduled Maintenance Services”
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant. When
the differential is cold, add enough lubricant to
raise the level to
1/2 inch (12 mm) below the filler
plug hole.
When the differential
is at operating temperature
(warm), add enough lubricant to raise the level
to the
bottom
of the filler plug hole.
What to use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See “Recommended Fluids and
Lubricants“
in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL J engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km) whichever occurs first, if you add only
DEX-COOL’ extended life coolant.
The following explains your cooling system and how
to add coolant when
it is low. If you have a problem
with engine overheating, see “Engine Overheating” in
the Index.
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A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
0- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use
a 50/50 mixture of clean water and
DEX-COOL@ coolant.
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Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow
of coolant through the radiator until the coolant
reaches a preset temperature.
Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is
a leak in the system or
you hear an unusual noise.
A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap and
the top
of the reservoir clean, then unscrew the cap and
wipe the dipstick with a clean rag. Replace the cap and
completely tighten it. Then remove the cap again and
look at the fluid level on the dipstick.
The level should be between the
ADD and FULL marks.
If necessary, add only enough fluid to bring the level up
to the proper range.
What to Use
To determine what kind of fluid to use, see
“Recommended Fluids and Lubricants” in the Index.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
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