2004 CHEVROLET IMPALA Owners Manual

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-3

Doing Your Own Service Work
If you want to do some of your own service work, you
will want to use the proper service manual. It tells
you much more about how to service your vehicle than
this manual can. To order the proper service manual,
seeService Publications Ordering Information on
page 7-12.
Your vehicle has an air bag system. Before attempting
to do your own service work, seeServicing Your
Air Bag-Equipped Vehicle on page 1-60.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-15.
{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.
CAUTION: (Continued)
CAUTION: (Continued)

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. “English” and “metric”
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 airow 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.
5-4

Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
If your vehicle has the 3400 V6 engine (VIN Code E) or
the 3800 V6 engine (VIN Code K), 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 this occurs, use a
gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might 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. If
you are using 87 octane or higher-octane fuel and you
hear heavy knocking, your engine needs service.
If your vehicle has the 3800 Supercharged V6 engine
(VIN Code 1), use only premium unleaded gasoline with a
posted octane of 91 or higher. In an emergency, you may
be able to use a lower octane — as low as 87 — if heavy
knocking does not occur. Rell your tank with premium
fuel as soon as possible. Otherwise, you might damage
your engine. If you are using 91 octane or higher-octane
fuel and you hear heavy knocking, your engine needs
service.
Gasoline Specications
It is recommended that gasoline meet specications
which were developed by automobile manufacturers
around the world and contained in the World-Wide
Fuel Charter which is available from the
Alliance of Automobile Manufacturers at
www.autoalliance.org/fuel_charter.htm. Gasoline
meeting these specications could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada, look for the
“Auto Makers’ Choice”
label on the pump.
Canada Only
5-5

California Fuel
If your vehicle is certied to meet California Emission
Standards (see the underhood emission control
label), it is designed to operate on fuels that meet
California specications. If this fuel is not available in
states adopting California emissions standards,
your vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction indicator
lamp may turn on (seeMalfunction Indicator Lamp
on page 3-37) 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.
Additives
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.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. General Motors
recommends that you buy gasolines that are advertised
to help keep fuel injectors and intake valves clean. If your
vehicle experiences problems due to dirty injectors or
valves, try a different brand of gasoline.
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 specications described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
5-6

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.
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 nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel.
Costly repairs caused by use of improper fuel would
not be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
Filling Your Tank
{CAUTION:
Fuel vapor burns violently and a fuel re can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions
on the pump island. Turn off your engine when
you are refueling. Do not smoke if you are near
fuel or refueling your vehicle. Keep sparks,
ames and smoking materials away from fuel.
Do not leave the fuel pump unattended when
refueling your vehicle — this is against the law
in some places. Keep children away from the
fuel pump; never let children pump fuel.
5-7

Turn your vehicle off to refuel.
The fuel cap is located behind a hinged door on the
driver’s side of the vehicle.While refueling, let the fuel cap hang by the tether
below the fuel ll opening.
To remove the fuel cap, turn it slowly to the left
(counterclockwise).
5-8

{CAUTION:
If you spill fuel and then something ignites it,
you could be badly burned. Fuel 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 “hiss” noise to stop.
Then unscrew the cap all the way.
Be careful not to spill fuel. Don’t top off or overll your
tank, and wait a few seconds after you’ve nished
pumping before you remove the nozzle. Clean fuel from
painted surfaces as soon as possible. SeeCleaning
the Outside of Your Vehicle on page 5-97. When lling
the tank do not overll by squeezing in much more
fuel after the pump shuts off.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. SeeMalfunction Indicator Lamp on
page 3-37.
{CAUTION:
If a re starts while you are refueling, do not
remove the nozzle. Shut off the ow of fuel by
shutting off the pump or by notifying the
station attendant. Leave the area immediately.
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 t properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. SeeMalfunction Indicator Lamp on
page 3-37.
5-9

Filling a Portable Fuel Container
{CAUTION:
Never ll 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 ll 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 ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, 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.
5-10