2002 PONTIAC GRAND PRIX Engine

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If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you've
pulled off the road and stopped carefully, have
the vehicle towed for service.
When the ignition is on, the brake system warning light
will also come on when you set your parking brake. The
light will stay on if your parking brake doesn't release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
Anti-Lock Brake System Warning Light
With the anti-lock brake
system, the light will
come on when your engine
is started and may stay
on for three seconds.
That's normal.
If the anti
-lock brake system warning light stays on
longer than normal after you've started your engine, turn
the ignition off. Or, if the light comes on and stays 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
light is on and the regular brake system warning light
isn't on, you still have brakes, but you don't have
anti
-lock brakes.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

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Traction Control System Warning Light
(3800 Supercharged V6 Engine Only)
The traction control
system warning light
may come on for the
following reasons:

If you turn the system off by pressing the TCS
button located on the far right side of the trip
computer, the warning light will come on and
stay on. To turn the system back on, press the
button again. The warning light should go off.
See ªTraction Control Systemº in the Index
for more information.

If there's a brake system problem that is specifically
related to traction control, the traction control system
will turn off and the warning light will come on. If
your brakes begin to overheat, the traction control
system will turn off and the warning light will come
on until your 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
(3100 V6 or 3800 V6 Engine)
The Enhanced Traction
System warning light
may come on for the
following reasons:

If you turn the system off by pressing the TRAC
button on the far right side of the Driver Information
Center or trip computer (if equipped), the warning
light will come on and stay on. To turn the system
back on, press the button again. The warning light
should go off. See ªEnhanced Traction Systemº in
the Index for more information.

If the Enhanced Traction System warning 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.

If the traction control system is affected by an
engine
-related problem, the system will turn off and
the warning light will come on.
When this warning light is on, the system will not limit
wheel spin. Adjust your driving accordingly.

2-83 Low Traction Light
If you have the Enhanced
Traction System or the
Traction Control System,
this light will also come
on when the system is
limiting wheel spin.
You may feel or hear the system working, but this is
normal. Slippery road conditions may exist if the low
traction light comes on, so adjust your driving
accordingly. The light will stay on for a few seconds
after the Enhanced Traction System or the Traction
Control System stops limiting wheel spin. See
ªEnhanced Traction Systemº or ªTraction Control
Systemº in the Index.
The low traction light also comes on briefly when you
turn the ignition key to RUN. If the light doesn't come
on then, have it fixed so it will be there to tell you when
the Traction Control System or Enhanced Traction
System is active.
Engine Coolant Temperature Light
This light tells 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 of the road, stop the
vehicle and turn off the engine as soon as possible.
See ªEngine Overheatingº in the Index.

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Engine Coolant Temperature Gage
United States Canada
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 same thing as the warning light.
It means that the engine coolant has overheated. If you
have been operating the vehicle under normal
conditions, you should pull off the road, stop the
vehicle, and turn off the engine as soon as possible.
See ªEngine Overheatingº in the Index.
Low Coolant Warning Light
If this light comes on,
the system is low on
coolant and the engine
may overheat.
See ªEngine Coolantº in the Index and have the vehicle
serviced as soon as possible.

2-85 Malfunction Indicator Lamp (Service
Engine Soon Light in the United States
or Check Engine Light in Canada)
United States Canada
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
SERVICE ENGINE SOON or 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:
Modifications 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 the SERVICE ENGINE SOON or
CHECK ENGINE light to come on.
Modifications 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 Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center 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 flashing and remains on steady, see ªIf
the Light Is On Steadyº following.
If the light continues to flash, 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 flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
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 ªFilling Your Tankº in the Index. 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.
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.

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Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make sure to install the fuel cap properly. See
ªFilling Your Tankº in the Index. It will take a few
driving trips to turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
ªFuelº in the Index. 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, misfiring, 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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix 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 in order to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
SERVICE ENGINE SOON or 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, see your dealer or qualified service center to
prepare the vehicle for inspection.

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Oil Pressure Light
United States Canada
If you have a problem with your oil pressure, this light
may stay on after you start your engine, or come on
when 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 fixed 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. Have it fixed right away.
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 fire. 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.