2001 GMC ENVOY coolant level

2-94
Engine Coolant Temperature Gage
United States Canada
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.
See ªEngine Overheatingº in the Index for
more information.
Malfunction Indicator Lamp
(Service Engine Soon Light in the United
States or Check Engine Light in Canada)
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 II (On
-Board
Diagnostics
-Second Generation) 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 or CHECK ENGINE
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.
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3-5
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 of the floor outlets.
As the interior temperature approaches a desired setting,
the fan speed will decrease. To maintain interior comfort,
the airflow will adjust between the instrument panel air
outlets and floor outlets. On bright sunny days in cool
weather, the airflow may come out of the air conditioning
and floor outlets (bi
-level mode) to maintain comfort and
prevent stuffiness.
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 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.
Mode Knob
- Manual Operation
The right knob on the control panel allows you to
choose the direction of air delivery.
You can choose to set the climate control system
operations yourself, or let the system work for you
by placing the system in AUTO mode. See ªMode
Knob
- Automatic Operationº earlier in this section.
VENT: This setting directs most of the air through
the instrument panel outlets and a small amount through
the floor outlets.
BI-LEVEL: This setting directs air through
the heater floor outlets as well as the instrument
panel outlets.
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3-7 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.
For quick cool
-down on very hot days, use MAX A/C
with the temperature knob turned to the left. 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 vehicles equipped with the Electronic Climate Control
system, this same performance can be achieved as long as
the A/C is on and the outside air button is not active.
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.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use HEATER with the
temperature knob turned clockwise. 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 ªEngine Coolant Heaterº in the Index.
Defogging and Defrosting
On cool, humid days, use BLEND to keep the
windshield and side windows clear.
Use DEFROST to remove fog or ice from the
windshield quickly in extreme humid or cold conditions.
Turn the temperature knob to the right and move the
fan knob toward high.
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4-55 Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have
extra wiring and a heavy
-duty turn signal flasher
(included in the optional trailering package).
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you're about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind you
are seeing your signal when they are not. It's important
to check occasionally to be sure the trailer bulbs are
still working.
Driving On Grades
Reduce speed and shift to a lower gear before 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.
If you have an automatic transmission, you should
use THIRD (3) when towing a trailer. Operating your
vehicle in THIRD (3) when towing a trailer will
minimize heat buildup and extend the life of your
transmission. Or, if you have a manual transmission,
it's better not to use FIFTH (5) gear, just drive in
FOURTH (4) gear (or, as you need to, a lower gear).
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 turn
your engine off immediately 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 (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine off.
If you do get the overheat warning, see ªEngine
Overheatingº in the Index.
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5-10
Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Cooling FanIf the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down.
When the engine is cold, 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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5-12 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,
drinkable water and DEX
-COOL
engine coolant at
the coolant recovery tank. See ªEngine Coolantº in the
Index for more information.
CAUTION:
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, drinkable water
and DEX
-COOL
coolant.
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.
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5-16
6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX
-COOL
coolant mixture
through the filler neck until the level reaches the
base of the filler neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure the
arrows on the pressure cap line up like this.
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6-
6-1
Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-6 Filling Your Tank
6
-8 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-11 Engine Oil
6
-16 Engine Air Cleaner/Filter
6
-17 Automatic Transmission Fluid
6
-20 Manual Transmission Fluid
6
-21 Hydraulic Clutch
6
-22 Rear Axle
6
-22 Four-Wheel Drive
6
-24 Engine Coolant
6
-27 Radiator Pressure Cap
6
-28 Power Steering Fluid
6
-28 Windshield Washer Fluid6
-30 Brakes
6
-34 Battery
6
-35 Bulb Replacement
6
-42 Windshield Wiper Blade Replacement
6
-44 Tires
6
-53 Appearance Care
6
-53 Cleaning the Inside of Your Vehicle
6
-56 Care of Safety Belts
6
-57 Cleaning the Outside of Your Vehicle
6
-61 GM Vehicle Care/Appearance Materials
6
-62 Vehicle Identification Number (VIN)
6
-62 Service Parts Identification Label
6
-63 Electrical System
6
-72 Replacement Bulbs
6
-72 Capacities and Specifications
6
-73 Normal Maintenance Replacement Parts
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