1998 GMC ENVOY heater

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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ProCarManuals.com

io Stea 5 Coming From Your Engine
~i you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get
a little too hot when you:
0 Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” in the Index.
If you get the overheat.warning with no sign of steam,
try this for a minute or
so:
1. Turn off your air conditioner.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D) or THIRD (3).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes.
Now see if the warning stops.
But then, if you still have the warning, turn ojfthe
engine nnd
get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
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When you decide it's safe to lift the hood, here's what
you'
I I see:
If the coolant inside the coolant recovery tank is boiling,
don't do anything else
until it cools down.
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
c.
I
The coolant level should be at least up to the
ADD mark.
If it isn't, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else
in
the cooling system.
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1 h CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is a leak.
If you run
the engine,
it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
NOTICE: I
Engine damage from running your engine
without coolant isn’t covered by your
1 warranty.
If there seems to be no leak, start the engine again. See
if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off
the engine.
How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t
at the ADD mark, add a 50/50 mixture of clean
brater (preferably distilled) and DEX-COOL@ engine
coolant at the coolant recovery tank. (See “Engine
Coolant”
in the Index for more information.)
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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NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
A CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
ADD r&ark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling system is cool before you do
it.
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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.
ProCarManuals.com

NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
Checking Coolant
When your engine is cold, the coolant level should be at
ADD, or a little higher. When your engine is warm, the
level should be up to
FULL HOT, or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the cwolarzt recovery tank.
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Climate Control System ........................... 3-2
Clock. Setting
................................... 3-8
Comfort Controls
................................ 3-2
Console Mounted CD Changer
.................... 3- 18
Content Theft-Deterrent
......................... 2- I 1
Control of a Vehicle .............................. 4-6
ConvenienceNet
............................... 2-46
Convex Outside Mirror
.......................... 2-42
Coolant
.................................. 5-14. 6.21
Coolant Heater. Engine .......................... 2- 16
Courtesy Transportation ........................... 8-8
Cruise Control
................................. 2-33
Customer Assistance Information
................... 8- 1
Customer Satisfaction Procedure .................... 8-2
Compact Disc Care
............................. 3-26
Dama. ue. Finish
............................... 6-52
Damage. Sheet Metal ............................ 6-5 1
Daytime Running Lamps ......................... 2-37
Dead Battery
................................... 5-3
Defects. Reporting Safety
........................ 8- IO
Defensive Driving ............................... 4-2
Defrosting
..................................... 3-6
Dimensions. Vehicle
............................ 6-62
Dome Lamps
.................................. 2-39
DoorLocks
..................................... 2-4
Drive
........................................ 2-19
Drive Axle Service
.............................. 7-44
Defogging
..................................... 3-6 Driver Information System
....................... 2-43
Driver Position
................................. i . 12
Driving
City
........................................ 4-31
Defensive
.................................... 4-2
Drunken ..................................... 4-3
Foreign Countries
.............................. 6-5
Freeway
.................................... 4-32
Guidelines
.................................. 4-14
Hill and Mountain Roads ....................... 4-34
In a Blizzard ................................. 4-38
Night
...................................... 4-27
Off-Road
................................... 4-15
OnCurves ...................................
4-9
Rainy Conditions ............................. 4-28
Snowy and Icy Conditions
...................... 4-36
Through Deep Standing Water
................... 4-30
WetRoads
.................................. 4-28
Winter
...................................... 4-36
With
a Trailer ................................ 4-48
Driving On Grades While Towing
a Trailer ........... 4-50
Drunken Driving
................................ 4-3
Electrical Equipment. Adding
............... 3.24. 6.54
Electrical System
............................... 6-54
Electrochomic Inside Day/Night Rearview Mirror
..... 2-40
Electronic Level Control
......................... 4-42
Engine
........................................ 6-9
Coolant Heater
............................... 2-16
Coolant Level Check
.......................... 7-39
Coolant Temperature Gage ..................... 2-66
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