2008 PONTIAC GRAND PRIX fuel pressure

If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.Your vehicle will not pass this inspection if the
OBD (on-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle
would be considered not ready for inspection. This can
happen if you have recently replaced the battery or
if the battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This can take several days
of routine driving. If you have done this and your
vehicle still does not pass the inspection for lack of
OBD system readiness, your dealer/retailer can
prepare the vehicle for inspection.
Oil Pressure Light
If there is a problem with
the vehicle’s oil pressure,
this light may stay on
when the engine is started.
It may also come on while the vehicle is being driven.
This indicates that the engine could be low on oil or could
have some other oil problem. Have it xed right away.
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CHECK GAS CAP
This message displays when the fuel cap is not on,
or is not fully tightened. Check the fuel cap to ensure it is
on and properly tightened. The diagnostic system can
determine if the fuel cap has been left off or improperly
installed. A loose or missing fuel cap allows fuel to
evaporate into the atmosphere. A few driving trips with
the cap properly installed should turn this message off.
SeeFilling the Tank on page 5-8for more information.
This message displays while the ignition is in ON/RUN.
A chime sounds for two seconds when this message
is displayed and then the message continues to display.
Press the set/reset button to acknowledge this
message and to clear it from the screen.
This message continues to display for three seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for three seconds if the
message has been acknowledged, but the condition
still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more than one tire
pressure message at a time. To read the other messages
that may have been sent at the same time, press the
set/reset button. If a tire pressure message appears on
the DIC, stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-62,Loading Your
Vehicle on page 4-22, andInflation - Tire Pressure on
page 5-69. The DIC also shows the tire pressure values.
SeeDIC Operation and Displays (Uplevel DIC with Trip
Computer) on page 3-55orDIC Operation and Displays
(Base Level DIC) on page 3-62. If the tire pressure is low,
the low tire pressure warning light comes on. SeeTire
Pressure Light on page 3-49.
This message displays while the ignition is in ON/RUN.
Press the set/reset button to acknowledge this
message and to clear it from the screen.
This message continues to display for three seconds
if it has not been acknowledged when the engine
is turned off. It also re-displays for three seconds if the
message has been acknowledged, but the condition
still exists when the engine is turned off.
If the condition still exists, the message re-appears
when the engine is turned on.
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Hydroplaning
Hydroplaning is dangerous. Water can build up
under your vehicle’s tires so they actually ride on the
water. This can happen if the road is wet enough
and you are going fast enough. When your vehicle is
hydroplaning, it has little or no contact with the road.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving
tips include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth.
SeeTires on page 5-62.
Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full?
Windows clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel?
Have up-to-date maps?
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Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-24
Pressure Cap...............................................5-27
Engine Overheating.......................................5-27Overheated Engine Protection
Operating Mode........................................5-29
Cooling System............................................5-30
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery........................................................5-45
Jump Starting...............................................5-46
Headlamp Aiming...........................................5-51
Bulb Replacement..........................................5-54
Halogen Bulbs..............................................5-54
Headlamps and Sidemarker Lamps.................5-54
Front Turn Signal, Parking and Fog Lamps......5-57
Taillamps, Turn Signal, and Stoplamps............5-58
Back-Up Lamps............................................5-59
License Plate Lamp......................................5-60
Replacement Bulbs.......................................5-60
Windshield Replacement.................................5-61
Windshield Wiper Blade Replacement..............5-61
Tires..............................................................5-62
Tire Sidewall Labeling...................................5-63
Tire Terminology and Denitions.....................5-66
Ination - Tire Pressure.................................5-69
Tire Pressure Monitor System.........................5-71
Section 5 Service and Appearance Care
5-1

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
B. Battery. SeeBattery on page 5-45.
C. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-124.
D. Remote Positive (+) Terminal. SeeJump Starting on
page 5-46.
E. Pressure Cap. SeePressure Cap on page 5-27.
F. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
G. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
H. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
I. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-22.
J. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
L. Engine Coolant Recovery Tank. SeeCooling System
on page 5-30.Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
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Cold Tire Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-69.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN), an
alphanumeric designator which can also identify the
tire manufacturer, production plant, brand, and date
of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading Your Vehicle on page 4-22.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on
page 4-22.GAWR RR
:Gross Axle Weight Rating for the rear
axle. SeeLoading Your Vehicle on page 4-22.
Intended Outboard Sidewall
:The side of
an asymmetrical tire, that must always face
outward when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT-Metric) Tire
:A tire used on
light duty trucks and some multipurpose passenger
vehicles.
Load Index
:An assigned number ranging from
1 to 279 that corresponds to the load carrying
capacity of a tire.
Maximum Ination Pressure
:The maximum air
pressure to which a cold tire can be inated.
The maximum air pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible ination pressure for
that tire.
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Treadwear Indicators:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. SeeWhen It Is Time for New Tires on
page 5-77.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-80.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
Your Vehicle on page 4-22.
Vehicle Maximum Load on the Tire
:Load on an
individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard
:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended ination pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 4-22.
Ination - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is
not. If your tires do not have enough air
(under-ination), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
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Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels. The
TPMS sensors monitor the air pressure in your vehicle’s
tires and transmit tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the size
indicated on the vehicle placard or tire ination pressure
label, you should determine the proper tire ination
pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one or
more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated tire
causes the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination has
not reached the level to trigger illumination of the TPMS
low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash for
approximately one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur for
a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly.
Always check the TPMS malfunction telltale after
replacing one or more tires or wheels on your vehicle to
ensure that the replacement or alternate tires and
wheels allow the TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-72for
additional information.
5-71