1999 PONTIAC GRAND PRIX check engine light

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Warning Lights, Gages
and Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to
your warning lights and gages could also save you or
others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle's functions. As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the
engine just to let you know they're working. If you are
familiar with this section, you should not be alarmed
when this happens.
Gages can indicate when there may be or is a problem
with one of your vehicle's functions. Often gages and
warning lights work together to let you know when
there's a problem with your vehicle.When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual's advice.
Waiting to do repairs can be costly
-- and even
dangerous. So please get to know your warning lights
and gages. They're a big help.
Your vehicle may also have a driver information system
that works along with the warning lights and gages.
See ªDriver Information Systemº in the Index.
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
come on for about eight seconds to remind people to
fasten their safety belts, unless the driver's safety belt is
already buckled.
The safety belt light will
also come on and stay on
for about 70 seconds, or
until the driver's seatbelt
is buckled.
If the driver's belt is already buckled, neither the chime
nor the light will come on.

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2-71 Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows SRS AIR BAG. The system checks
the air bag's electrical system for malfunctions. The
light tells you if there is an electrical problem. The
system check includes the air bag sensors, the air bag
modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, see ªAir Bagº in the Index.
This light will come on
when you start your engine,
and it will flash for a few
seconds. Then the light
should go out. This means
the system is ready.
If the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds 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.
Charging System Light
The charging system light
will come on briefly when
you turn on the ignition, as
a check to show you it's
working. Then it will
go out.
If it stays on, or comes on while you are driving, you
may have a problem with the charging system. It could
indicate that you have a loose drive belt or another
electrical problem. Have it checked right away. Driving
while this light is on could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.

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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.

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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.
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.

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2-78 Oil Warning Light
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 is
working, but the light will go out when you turn the
ignition to START. 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.

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2-79 Low Oil Level Light
The engine is equipped with
an oil level monitoring
system. When the ignition
key is turned to ON, the
LOW OIL LEVEL light
will briefly flash.
If the light does not flash, have it fixed so it will be
ready to warn you if there's a problem.
If the light stays on, stop the vehicle on a level surface
and turn the engine off. Check the oil level using the
engine oil dipstick. (See ªEngine Oilº in the Index.)
The oil level monitoring system only checks oil level
during the brief period when the ignition key is between
RUN and START. It does not monitor engine oil level
when the engine is running. Additionally, an oil level
check is only performed if the engine has been turned
off for a considerable period of time, allowing the oil
normally in circulation to drain back into the oil pan.
Engine Coolant Temperature 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.
In ªProblems on the Road,º this manual shows what to
do. See ªEngine Overheatingº in the Index.

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Avoid needless heavy braking. Some people drive in
spurts
-- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic.
This is a mistake. Your brakes may not have time to
cool between hard stops. Your brakes will wear out
much faster if you do a lot of heavy braking. If you
keep pace with the traffic and allow realistic following
distances, you will eliminate a lot of unnecessary
braking. That means better braking and longer
brake life.
If your engine ever stops while you're driving, brake
normally but don't pump your brakes. If you do, the
pedal may get harder to push down. If your engine
stops, you will still have some power brake assist. But
you will use it when you brake. Once the power assist is
used up, it may take longer to stop and the brake pedal
will be harder to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is an
advanced electronic braking system that will help
prevent a braking skid.
When you start your engine, or when you begin to drive
away, your anti
-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on, and you may even notice that your
brake pedal moves or pulses a little. This is normal.
If there's a problem with the
anti
-lock brake system, this
warning light will stay on.
See ªAnti
-Lock Brake
System Warning Lightº in
the Index.

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Tie a red cloth to your vehicle to alert police that
you've been stopped by the snow.

Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make body
insulators from newspapers, burlap bags, rags, floor
mats
-- anything you can wrap around yourself or
tuck under your clothing to keep warm.
You can run the engine to keep warm, but be careful.
CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.