gas GMC ENVOY 2002 User Guide

6-3
CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.

Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Gasoline Octane
Use regular unleaded gasoline with a posted octane
of 87 or higher. If the octane is less than 87, you may
get a heavy knocking noise when you drive. If it is bad
enough, it can damage your engine. A little pinging
noise when you accelerate or drive uphill is considered
normal. This does not indicate a problem exists or that
a higher
-octane fuel is necessary.

6-4 Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers' Association for better
vehicle performance and engine protection. Gasolines
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasolines.
In Canada, look for
the ªAuto Makers'
Choiceº label on
the pump.
Canada Only
California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specifications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see ªMalfunction Indicator Lampº in the Index)
and your vehicle may fail a smog
-check test. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered by
your warranty.

6-5 Additives
Some gasolines that are not reformulated for low
emissions may contain an octane
-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may be
affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly.
You should not have to add anything to your fuel.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available
in your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly
if they comply with the specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don't use fuel containing
methanol. It can corrode metal parts in your
fuel system and also damage plastic and rubber
parts. That damage wouldn't be covered under
your warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to find. Never use leaded gasoline or any other fuel not
recommended in the previous text on fuel. Costly repairs
caused by use of improper fuel wouldn't be covered by
your warranty.
To check on fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you'll be driving.

6-6
Filling Your Tank
CAUTION:
Gasoline vapor is highly flammable. It burns
violently, and that can cause very bad injuries.
Don't smoke if you're near gasoline or refueling
your vehicle. Keep sparks, flames and smoking
materials away from gasoline.
The fuel cap is located behind a hinged door on driver's
side of your vehicle.
While refueling, hang the fuel cap by the tether using
the hook located on the inside of the filler door.
To remove the fuel cap, turn it slowly to the left
(counterclockwise). The fuel cap has a spring in it; if
you let go of the cap too soon, it will spring back to
the right.

6-7
CAUTION:
If you get gasoline on yourself and then
something ignites it, you could be badly burned.
Gasoline can spray out on you if you open the
fuel cap too quickly. This spray can happen if
your tank is nearly full, and is more likely in hot
weather. Open the fuel cap slowly and wait for
any ªhissº noise to stop. Then unscrew the cap all
the way.
Be careful not to spill gasoline. Clean gasoline from
painted surfaces as soon as possible. See ªCleaning the
Outside of Your Vehicleº in the Index.When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make sure
you fully install the cap. The diagnostic system can
determine if the fuel cap has been left off or improperly
installed. This would allow fuel to evaporate into the
atmosphere. See ªMalfunction Indicator Lampº in
the Index.
NOTICE:
If you need a new fuel cap, be sure to get the
right type. Your dealer can get one for you. If you
get the wrong type, it may not fit properly. This
may cause your malfunction indicator lamp to
light and may damage your fuel tank and
emissions system. See ªMalfunction Indicator
Lampº in the Index.

6-8
Filling a Portable Fuel Container
CAUTION:
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from the
container can ignite the gasoline vapor. You can
be badly burned and your vehicle damaged if this
occurs. To help avoid injury to you and others:

Dispense gasoline only into
approved containers.

Do not fill a container while it is inside a
vehicle, in a vehicle's trunk, pickup bed or
on any surface other than the ground.

Bring the fill nozzle in contact with the
inside of the fill opening before operating
the nozzle. Contact should be maintained
until the filling is complete.

Don't smoke while pumping gasoline.
Checking Things Under the Hood
CAUTION:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.

6-13 What Kind of Engine Oil to Use
Oils recommended for your vehicle can be identified by
looking for the starburst symbol.
This symbol indicates that the oil has been certified by
the American Petroleum Institute (API). Do not use any
oil which does not carry this starburst symbol.
If you change your own oil,
be sure you use oil that has
the starburst symbol on the
front of the oil container. If
you have your oil changed
for you, be sure the oil put
into your engine is
American Petroleum
Institute certified for
gasoline engines.
You should also use the proper viscosity oil for your
vehicle, as shown in the following chart:

6-14
As in the chart shown previously, SAE 5W-30 is best for
your vehicle. However, you can use SAE 10W
-30 if it's
going to be 0F (
-18C) or above. These numbers on an
oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE 20W
-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
starburst symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench
oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20F (-29C), consider using either an SAE 5W-30
synthetic oil or an SAE 0W
-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for good
performance and engine protection.
When to Change Engine Oil
(GM Oil Life System )
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly,
you must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENG OIL light in the Driver
Information Center (DIC) will come on. Change your oil
as soon as possible within the next two times you stop
for fuel. It is possible that, if you are driving under the
best conditions, the oil life system may not indicate that
an oil change is necessary for over a year. However,
your engine oil and filter must be changed at least once
a year and at this time the system must be reset. It is also
important to check your oil regularly and keep it at the
proper level.

6-33
Battery
Your new vehicle comes with a maintenance free
ACDelco
battery. When it's time for a new battery, get
one that has the replacement number shown on the
original battery's label. We recommend an ACDelco
battery. See ªEngine Compartment Overviewº in the
Index for battery location.
WARNING: Battery posts, terminals and related
accessories contain lead and lead compounds, chemicals
known to the State of California to cause cancer and
reproductive harm. Wash hands after handling.
Vehicle Storage
If you're not going to drive your vehicle for 25 days or
more, remove the black, negative (
-) cable from the
battery. This will help keep your battery from
running down.
CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren't careful. See ªJump Startingº in the Index
for tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your vehicle
for longer storage periods.
Also, for your audio system, see ªTheft
-Deterrent
Featureº in the Index.
Bulb Replacement
For the type of bulbs, see ªReplacement Bulbsº in
the Index.
For any bulb changing procedure not listed in this
section, contact your dealer.

6-34 Halogen Bulbs
CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
1. Open the hood.
2. Lift the inner quick release clips.
3. Pull the headlamp assembly away from the vehicle.
4. Remove the cover from the headlamp bulb.
5. Disconnect the wiring harness.
6. Remove the headlamp bulb by turning the socket
counterclockwise.
7. To install the replacement bulb, reverse
Steps 1 through 6.
Front Turn Signals and Sidemarker Lamps
Follow the same procedure listed for headlamp removal
earlier in this section. Replace the turn signal or
sidemarker bulb instead.
Taillamps and Rear Turn Signals
1. Open the liftgate.
2. Remove the two screws
from the lamp assembly.
3. Pull the assembly away from the vehicle.