2004 PONTIAC GRAND PRIX engine

{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not in¯ate in a crash, or they
could even in¯ate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the air bag
readiness light stays on after you start your
vehicle.
The air bag readiness light should ¯ash for a few
seconds when you turn the ignition key to RUN. If the
light doesn't come on then, have it ®xed so it will
be ready to warn you if there is a problem.
Up-Shift Light
This symbol can appear
on the instrument panel
if the vehicle has a
supercharged engine and
the shift lever is in the
MANUAL (M) transaxle
position.
It will appear as a prompt to up-shift to the next gear
using one of the TAP-ShiftŸ paddles located on
the steering wheel.
This symbol will also appear on the Head Up
Display (HUD).
See
Automatic Transaxle Operation on page 2-22for
more information.
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Anti-Lock Brake System Warning
Light
If your vehicle has the
Anti-lock Brake System
(ABS), this light will come
on when your engine is
started and may stay on
for several seconds.
That's normal.
If the ABS warning light comes on and stays on, there
may be a problem with the anti-lock portion of the brake
system. If the brake system warning light is not on,
you still have brakes, but you don't have anti-lock
brakes. See
Brake System Warning Light on page 3-36.If the light stays on, turn the ignition to OFF. If the light
comes on when you're driving, stop as soon as
possible and turn the ignition off. Then start the engine
again to reset the system. If the light still stays on,
or comes on again while you're driving, your vehicle
needs service. If the regular brake system warning light
isn't on, you still have brakes, but you don't have
anti-lock brakes. If the brake system warning light is
also on, you don't have anti-lock brakes and there's a
problem with your regular brakes. See
Brake System
Warning Light on page 3-36.
The anti-lock brake system warning light will come on
brie¯y when you turn the ignition key to RUN. This
is normal. If the light doesn't come then, have it ®xed
so it will be ready to warn you if there is a problem.
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Traction Control System (TCS)
Warning Light
If your vehicle has a 3800
V6 supercharged engine,
it may have the Traction
Control System (TCS).
This light may come on for the following reasons:
·If you turn the system off by pressing the TC (traction
control) button located on the center console, the
light will come on and stay on. To turn the system
back on, press the button again and the warning light
should go out. See
Traction Control System (TCS)
on page 4-10for more information.
·If there's a brake system problem that is speci®cally
related to traction control, the TCS will turn off and
the warning light will come on. If your brakes begin to
overheat, the TCS will turn off and the warning light
will come on until the brakes cool down.
If the traction control system warning light comes on
and stays on for an extended period of time when the
system is turned on, your vehicle needs service.
Enhanced Traction System Warning
Light
If your vehicle has the
3800 V6 engine and
the Enhanced Traction
System (ETS), this
light may come on for
the following reason.
·If you turn the system off by pressing the TC (traction
control) button located on the center console, this
light will come on and stay on. To turn the system
back on, press the button again and the warning light
should turn off. See
Enhanced Traction System
(ETS) on page 4-11.
·If the system is affected by an engine-related
problem, the system will turn off and the warning light
will come on.
If the light comes on and stays on for an extended
period of time when the system is turned on, your
vehicle needs service. Adjust your driving accordingly.
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Engine Coolant Temperature
Warning Light
This light tells you that
the engine coolant has
overheated or the radiator
cooling fan is not working.
If you have been operating the vehicle under normal
driving conditions, you should pull off the road, stop the
vehicle, and turn off the engine as soon as possible.
See
Cooling System on page 5-32for more information.
Engine Coolant Temperature Gage
Your vehicle has a gage
that shows the engine
coolant temperature.
If the gage pointer moves into the shaded area,
the engine is too hot. That reading means the engine
coolant has overheated. If you have been operating the
vehicle under normal driving conditions, you should
pull off the road, stop the vehicle, and turn off the engine
as soon as possible.
See
Cooling System on page 5-32for more information.
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Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on
to indicate that there is a problem and service is
required. Malfunctions often will be indicated by the
system before any problem is apparent. This may
prevent more serious damage to your vehicle. This
system is also designed to assist your service technician
in correctly diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that
may not be covered by your warranty.
Notice:Modi®cations made to the engine,
transaxle, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle's emission
controls and may cause this light to come on.
Modi®cations to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
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This light should come on, as a check to show you it
is working, when the ignition is on and the engine is not
running. If the light doesn't come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required.
·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
·Reducing vehicle speed.
·Avoiding hard accelerations.
·Avoiding steep uphill grades.
·If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.If the light stops ¯ashing and remains on steady,
see ªIf the Light Is On Steadyº following.
If the light continues to ¯ash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see ªIf the
Light Is On Steadyº following. If the light is still ¯ashing,
follow the previous steps, and see your dealer for
service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. See
Filling Your Tank on page 5-7.
The diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
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Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
See
Gasoline Octane on page 5-4. Poor fuel quality
will cause your engine not to run as efficiently as
designed. You may notice this as stalling after start-up,
stalling when you put the vehicle into gear, mis®ring,
hesitation on acceleration or stumbling on acceleration.
(These conditions may go away once the engine is
warmed up.) This will be detected by the system and
cause the light to turn on.
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 can check the vehicle. Your dealer has the
proper test equipment and diagnostic tools to ®x any
mechanical or electrical problems that may have
developed.
Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
may 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 your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may 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 GM dealer can prepare the
vehicle for inspection.
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Oil Pressure Light
If you have a problem with
your oil pressure, this light
may stay on after you
start the engine, or it may
come on while you are
driving.
This indicates that oil is not going through your engine
quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil
problem. Have it ®xed right away.
The oil light could also come on in two other situations:
·When the ignition is on but the engine is not running,
the light will come on as a test to show you it's
working. The light will go out when you turn the
ignition to RUN. If it doesn't come on with the ignition
on, you may have a problem with the fuse or bulb.
See
Fuses and Circuit Breakers on page 5-99.
·If you make a hard stop, the light may come on for
a moment. This is normal.
{CAUTION:
Don't keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches ®re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Damage to your engine from neglected
oil problems can be costly and is not covered
by your warranty.
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