2008 PONTIAC GRAND PRIX air condition

Engine Air Cleaner/Filter
The engine air cleaner/lter is located in the engine
compartment on the driver’s side of the vehicle.
SeeEngine Compartment Overview on page 5-12for
more information on location.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after each
50,000 mile (80 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information. If you
are driving in dusty/dirty conditions, inspect the lter
at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/lter, remove the lter from
the vehicle and lightly shake the lter to release loose
dust and dirt. If the lter remains caked with dirt, a new
lter is required.
To inspect or replace the engine air cleaner/lter do the
following:
3.8L V6 Engine
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If an overheat warning occurs without any sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the heater at the highest setting and the fan at
the highest speed and open the windows as
necessary.
If the overheat warning no longer exists, the vehicle can
be driven. Just to be safe, drive slower for about
10 minutes. If the warning does not come back on, the
vehicle can be driven normally.
If the warning continues, and you have not stopped, pull
over, stop, and park the vehicle right away.
If there is still no sign of steam, idle the engine for three
minutes while parked. If the warning is still there, turn off
the engine and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine Protection
Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode
The overheated engine protection operating mode
allows the vehicle to be driven to a safe place in an
emergency situation. If an overheated engine condition
exists, this protection mode alternates ring groups
of cylinders to help prevent engine damage. In this
mode, there will be a signicant loss in power and engine
performance. The engine coolant temperature gage
indicator will move to the shaded area, and the engine
coolant temperature warning light will come on, showing
that an overheated engine condition exists. Driving
extended miles (km) and/or towing a trailer in the
overheated engine protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss, change the oil and
reset the oil life system. SeeEngine Oil on page 5-15.
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Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads are
needed. The sound can come and go or be heard all the
time your vehicle is moving, except when you are pushing
on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-128.
Brake linings should always be replaced as complete
axle sets.
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(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio
:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire’s sidewall is 60 percent as high as
it is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:These characters
represent the load range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is the
maximum speed a tire is certied to carry a load.
Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
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Federal Communications Commission
(FCC) and Industry and Science
Canada
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with RSS-210 of
Industry and Science Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS) is designed
to warn the driver when a low tire pressure condition
exists. TPMS sensors are mounted onto each tire and
wheel assembly, excluding the spare tire and wheel
assembly. The TPMS sensors monitor the air pressure in
the vehicle’s tires and transmits the tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light,
located in the instrument
panel cluster.
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At the same time a message to check the pressure in a
specic tire appears on the Driver Information center
(DIC) display. The low tire pressure warning light and
the DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.
Using the DIC buttons, tire pressure readings can be
viewed by the driver. For additional information and
details about the DIC operation and displays seeDIC
Operation and Displays (Uplevel DIC with Trip Computer)
on page 3-55orDIC Operation and Displays (Base Level
DIC) on page 3-62andDIC Warnings and Messages on
page 3-67.
The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then turn
off as you start to drive. This could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inated to the proper pressure.A tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for your
vehicle’s tires when they are cold. SeeLoading Your
Vehicle on page 4-22, for an example of the Tire and
Loading Information label and its location on your vehicle.
Also seeInflation - Tire Pressure on page 5-69.
Your vehicle’s TPMS system can warn you about a low
tire pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation on
page 5-75andTires on page 5-62.
Your vehicle, when new, may have included a
factory-installed Tire Inator Kit. This kit uses a GM
approved liquid tire sealant. SeeTire Sealant and
Compressor Kit (GXP) on page 5-86.
Notice:Using non-approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using
an incorrect tire sealant is not covered by the
vehicle warranty. Always use the GM approved tire
sealant available through your dealer/retailer.
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TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to
come on are:
One of the road tires has been replaced with the
spare tire and wheel. The spare, if your vehicle has
one, does not have a TPMS sensor. The TPMS
malfunction light and DIC message should go off
once you re-install the road tire containing the
TPMS sensor.
The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in this
section.
One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your
dealer/retailer for service.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tire and
wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 5-78.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal
a low tire condition. See your dealer/retailer for service if
the TPMS malfunction light and DIC message comes on
and stays on.
TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you replace one or more of the TPMS sensors
or rotate the vehicle’s tires, the identication codes need
to be matched to the new tire/wheel position. The sensors
are matched, to the tire/wheel positions, in the following
order: driver side front tire, passenger side front tire,
passenger side rear tire, and driver side rear tire using a
TPMS diagnostic tool. See your dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. When increasing the tire’s pressure, do not
exceed the maximum ination pressure indicated on the
tire’s sidewall. To decrease the tire’s air-pressure use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
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When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
inuence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.You need new tires if any of the following statements
are true:You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if
your vehicle has one. Multiple conditions affect how fast
this aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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