2008 PONTIAC G8 engine

Gasoline Octane
If your vehicle has a V8 engine, use
regular unleaded gasoline with a
posted octane rating of 87 or higher.
If the octane rating is less than 87,
you might notice an audible
knocking noise when you drive,
commonly referred to as spark
knock. If this occurs, use a gasoline
rated at 87 octane or higher as
soon as possible. If you are using
gasoline rated at 87 octane or higher
and you hear heavy knocking, the
engine needs service.
If your vehicle has the 3.6L V6
engine (VIN Code 7), use regular
unleaded gasoline with a posted
octane rating of 87 or higher.
For best performance or trailer
towing, you could choose to
use middle grade 89 octane
unleaded gasoline. If the octane
rating is less than 87, you might
notice an audible knocking noise
when you drive, commonly referred
to as spark knock.If this occurs, use a gasoline rated
at 87 octane or higher as soon
as possible. If you are using
gasoline rated at 87 octane or higher
and you hear heavy knocking, the
engine needs service.
Gasoline Specications
At a minimum, gasoline should
meet ASTM specication D 4814
in the United States or
CAN/CGSB-3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. SeeAdditives on
page 8-34for additional information.
California Fuel
If your vehicle is certied to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specications.
See the underhood emission control
label. 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 might be affected.
The malfunction indicator lamp could
turn on and your vehicle might fail
a smog-check test. SeeMalfunction
Indicator Lamp on page 4-18.
If this occurs, return to your
authorized dealer/retailer for
diagnosis. If it is determined that the
condition is caused by the type of
fuel used, repairs might not be
covered by the vehicle warranty.
Driving and Operating 8-33
2008 - Pontiac G8 Owner Manual

Additives
To provide cleaner air, all gasolines
in the United States are now required
to contain additives that help prevent
engine and fuel system deposits
from forming, allowing the emission
control system to work properly.
In most cases, you should not have
to add anything to the fuel. However,
some gasolines contain only the
minimum amount of additive required
to meet U.S. Environmental
Protection Agency regulations.
To help keep fuel injectors and intake
valves clean, or if your vehicle
experiences problems due to dirty
injectors or valves, look for gasoline
that is advertised as TOP TIER
Detergent Gasoline. Also, your
dealer/retailer has additives that will
help correct and prevent most
deposit-related problems.
Gasolines containing oxygenates,
such as ethers and ethanol, and
reformulated gasolines might
be available in your area.We recommend that you use these
gasolines, if they comply with the
specications described earlier.
However, E85 (85% ethanol) and
other fuels containing more than
10% ethanol must not be used in
vehicles that were not designed
for those fuels.
Notice:Your vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under your
warranty.
Some gasolines that are not
reformulated for low emissions can
contain an octane-enhancing additive
called methylcyclopentadienyl
manganese tricarbonyl (MMT); ask
the attendant where you buy gasoline
whether the fuel contains MMT.We recommend against the use of
such gasolines. Fuels containing
MMT can reduce the life of spark
plugs and the performance of the
emission control system could be
affected. The malfunction indicator
lamp might turn on. If this occurs,
return to your dealer/retailer for
service.
Fuels in Foreign
Countries
If you plan on driving in another
country outside the United States or
Canada, the proper fuel might 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.
8-34 Driving and Operating
2008 - Pontiac G8 Owner Manual

Filling the 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.
Do not use cellular phones.
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. Do not re-enter
the vehicle while pumping fuel.
Keep children away from the
fuel pump; never let children
pump fuel.The fuel cap is located behind a
hinged fuel door on the driver side
of the vehicle.
To open the fuel door the vehicle
must be unlocked. Push on the rear
edge of the door to open.
When reinstalling the cap, turn it
clockwise until it clicks, otherwise
the Malfunction Indicator Lamp may
turn on. SeeMalfunction Indicator
Lamp on page 4-18.
{CAUTION
Fuel can spray out on you if
you open the fuel cap too
quickly. If you spill fuel and
then something ignites it, you
could be badly burned. 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. Do not
top off or overll the tank and
wait a few seconds after you have
nished pumping before removing
the nozzle. Clean fuel from painted
surfaces as soon as possible.
SeeExterior Cleaning on page 9-94.
When replacing the fuel cap,
turn it clockwise until it clicks.
Make sure the cap is fully installed.
Driving and Operating 8-35
2008 - Pontiac G8 Owner Manual

Vehicle Service
and Care
Service
Service...............................9-2
Accessories and
Modications.....................9-3
California Proposition 65
Warning............................9-3
California Perchlorate
Materials Requirements.....9-3
Doing Your Own
Service Work....................9-4
Adding Equipment to the
Outside of the Vehicle......9-4
Owner Checks
Owner Checks....................9-5
Hood Release.....................9-5
Engine Compartment
Overview...........................9-6
Engine Oil..........................9-8
Engine Oil Life System.....9-10
Engine Air Cleaner/Filter. . .9-11
Automatic Transmission
Fluid................................9-13
Engine Coolant.................9-13
Radiator Pressure Cap......9-15
Engine Overheating...........9-16
Cooling System.................9-17
Power Steering Fluid.........9-21
Windshield Washer Fluid. . .9-22
Windshield Wiper Blade
Replacement...................9-23
Brakes..............................9-24
Battery..............................9-26
Headlamp Aiming
Headlamp Aiming..............9-27
Bulb Replacement
Bulb Replacement.............9-29
Halogen Bulbs..................9-29
Headlamps and Parking
Lamps.............................9-29
Taillamps..........................9-31
Replacement Bulbs...........9-32
Electrical System
Add-On Electrical
Equipment.......................9-32
Headlamp Wiring..............9-33
Windshield Wiper Fuses. . . .9-33
Power Windows and
Other Power Options. . . . . . .9-33
Instrument Panel Fuse
Block...............................9-33
Engine Compartment
Fuse Block......................9-35
Rear Compartment Fuse
Block...............................9-38
Tires
Tires.................................9-39
Tire Sidewall Labeling. . . . . . .9-40
Tire Terminology and
Denitions.......................9-43
Ination - Tire Pressure. . . .9-46
High-Speed Operation. . . . . . .9-48
Tire Pressure Monitor
System............................9-49
Tire Pressure Monitor
Operation........................9-51
Tire Inspection and
Rotation..........................9-54
When It Is Time for
New Tires.......................9-56
Buying New Tires.............9-56
Different Size Tires and
Wheels............................9-58
Vehicle Service and Care 9-1
2008 - Pontiac G8 Owner Manual

Uniform Tire Quality
Grading...........................9-59
Wheel Alignment and Tire
Balance...........................9-60
Wheel Replacement..........9-61
Tire Chains.......................9-62
Tire Changing
If a Tire Goes Flat............9-62
Tire Sealant and
Compressor Kit
(V8 Engine)
.....................9-64
Changing a Flat Tire
(V6 Engine).....................9-71
Removing the Spare Tire
and Tools........................9-72
Removing the Flat Tire
and Installing the
Spare Tire
.......................9-73
Storing a Flat or Spare
Tire and Tools.................9-78
Compact Spare Tire..........9-79
Jump Starting
Jump Starting...................9-80
Towing
Towing Your Vehicle.........9-84
Shift Lock Manual
Release...........................9-84
Recreational Vehicle
Towing............................9-85
Towing a Trailer................9-85
Appearance Care
Interior Cleaning................9-91
Exterior Cleaning..............9-94
Sheet Metal Damage........9-98
Finish Damage..................9-98
Underbody Maintenance. . . .9-98
Chemical Paint Spotting. . . .9-98
Vehicle Care/Appearance
Materials.........................9-99
Service
For service and parts needs, visit
your dealer/retailer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one
of these marks:
9-2 Vehicle Service and Care
2008 - Pontiac G8 Owner Manual

Accessories and
Modications
When non-dealer/non-retailer
accessories are added to your
vehicle they can affect your vehicle’s
performance and safety, including
such things as, airbags, braking,
stability, ride and handling,
emissions systems, aerodynamics,
durability, and electronic systems
like antilock brakes, traction control
and stability control. Some of
these accessories could even cause
malfunction or damage not
covered by warranty.
GM Accessories are designed to
complement and function with other
systems on your vehicle. Your
GM dealer/retailer can accessorize
your vehicle using genuine GM
Accessories. When you go to yourGM dealer/retailer and ask for GM
Accessories, you will know that
GM-trained and supported service
technicians will perform the
work using genuine GM
Accessories.
Also, seeAdding Equipment to Your
Airbag-Equipped Vehicle on
page 1-30.
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.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained
in remote keyless entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Vehicle Service and Care 9-3
2008 - Pontiac G8 Owner Manual

Owner Checks
{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.
Hood Release
To open the hood:
1. Pull the release handle with the
above symbol on it. It is located
below the instrument panel to
the left of the steering wheel.2. Pull up on the secondary hood
release. The lever is located
near the middle of the hood.
3. Lift the hood.
4. Release the hood prop rod from
its retainer and put it into the
slot in the hood. To insert
the hood prop rod into the slot.
Before closing the hood, be sure all
the ller caps are on properly.
Make sure to return the hood prop
rod carefully back to its retainer
to avoid damaging the vehicle.
Vehicle Service and Care 9-5
2008 - Pontiac G8 Owner Manual

Engine Compartment Overview
When you open the hood, this is what you will see:A. Engine Compartment Fuse
Block. See Engine Compartment
Fuse Block on page 9-35 .
B. Coolant Reservoir and Dipstick. See Cooling System on
page 9-17 .
C. Engine Oil Fill Cap. See “When to Add Engine Oil” under Engine
Oil on page 9-8 .
D. Engine Oil Dipstick (Out of View). See “Checking Engine Oil” under
Engine Oil on page 9-8 .
E. Brake Master Cylinder Reservoir. See “Brake Fluid” under Brakes
on page 9-24 .
F. Power Steering Reservoir. See Power Steering Fluid on
page 9-21 .
G. Engine Air Cleaner/Filter. See Engine Air Cleaner/Filter
on page 9-11 .
H. Windshield Washer Fluid Reservoir. See Windshield
Washer Fluid on page 9-22 .
I. Radiator Pressure Cap. See Cooling System on page 9-17 .
V6 Engine
9-6 Vehicle Service and Care
2008 - Pontiac G8 Owner Manual