2012 CHEVROLET IMPALA check engine

Black plate (17,1)Chevrolet Impala Owner Manual - 2012
Instruments and Controls 5-17
Notice:Modifications made to the
engine, transmission, exhaust,
intake, or fuel system of the
vehicle or the replacement of the
original tires with other than
those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by the
vehicle warranty. This could also
result in a failure to pass a
required Emission Inspection/
Maintenance test. See
Accessories and Modifications on
page 10‑3.
This light comes on during a
malfunction in one of two ways:
Light Flashing: A misfire condition
has been detected. A misfire
increases vehicle emissions and
could damage the emission control
system on the vehicle. Diagnosis
and service might be required. To prevent more serious damage to
the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the
amount of cargo being hauled as
soon as it is possible.
If the light continues to flash, stop
and park the vehicle. Turn the
vehicle off, wait at least 10 seconds,
and restart the engine. If the light is
still flashing, follow the previous
steps and see your dealer for
service as soon as possible.
Light On Steady: An emission
control system malfunction has
been detected on the vehicle.
Diagnosis and service might be
required. The following may correct an
emission system malfunction:
.Check that the fuel cap is fully
installed. See
Filling the Tank on
page 9‑40. 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 the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up.

Black plate (18,1)Chevrolet Impala Owner Manual - 2012
5-18 Instruments and Controls
If one or more of these conditions
occurs, change the fuel brand used.
It will require at least one full tank of
the proper fuel to turn the light off.
SeeRecommended Fuel on
page 9‑37.
If none of the above have made the
light turn off, your dealer can check
the vehicle. The dealer has the
proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.
Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For the
inspection, the emission system test
equipment is connected to the
vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUN
while the engine is off.
.The OBD II (On-Board
Diagnostics) system determines
that critical emission control
systems have not been
completely diagnosed. The
vehicle would be considered not
ready for inspection. This can
happen if the 12-volt battery has
recently been replaced or 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 this has been done and the
vehicle still does not pass the
inspection for lack of OBD II
system readiness, your dealer
can prepare the vehicle for
inspection.

Black plate (22,1)Chevrolet Impala Owner Manual - 2012
5-22 Instruments and Controls
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine is
started. It provides information
about tire pressures and the TPMS.
When the Light Is On Steady
This indicates that one or more of
the tires are significantly
underinflated.A tire pressure message can
accompany the light. See
Tire
Messages on page 5‑36 for more
information. Stop as soon as
possible, and inflate the tires to the
pressure value shown on the Tire
and Loading Information label. See
Tire Pressure on page 10‑41 for
more information.
When the Light Flashes First and
Then Is On Steady
This indicates that there may be a
problem with the TPMS. The light
flashes for about a minute and stays
on steady for the remainder of the
ignition cycle. This sequence
repeats with every ignition cycle.
See Tire Pressure Monitor
Operation on page 10‑44 for more
information.
Engine Oil Pressure Light
{WARNING
Do not keep driving if the oil
pressure is low. The engine can
become so hot that it catches fire.
Someone could be burned. Check
the oil as soon as possible and
have the vehicle serviced.
Notice: Lack of proper engine oil
maintenance can damage the
engine. The repairs would not be
covered by the vehicle warranty.
Always follow the maintenance
schedule for changing engine oil.

Black plate (32,1)Chevrolet Impala Owner Manual - 2012
5-32 Instruments and Controls
OIL PRESSURE LOW STOP
ENGINE
Notice:If you drive the vehicle
while the engine oil pressure is
low, severe engine damage may
occur. If a low oil pressure
warning appears on the Driver
Information Center (DIC), stop the
vehicle as soon as possible. Do
not drive the vehicle until the
cause of the low oil pressure is
corrected. See Engine Oil on
page 10‑7 for more information.
This message displays when the
vehicle's engine oil pressure is low.
The oil pressure light also appears
on the instrument panel cluster. See
Engine Oil Pressure Light on
page 5‑22.
Stop the vehicle immediately, as
engine damage can result from
driving a vehicle with low oil
pressure. Have the vehicle serviced
by your dealer as soon as possible
when this message is displayed.
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays when the
vehicle's engine power is reduced.
Reduced engine power can affect
the vehicle's ability to accelerate.
If this message is on, but there
is no reduction in performance,
proceed to your destination. The
performance may be reduced the
next time the vehicle is driven. The
vehicle may be driven at a reduced
speed while this message is on, but
acceleration and speed may be
reduced. Anytime this message
stays on, the vehicle should be
taken to your dealer for service as
soon as possible.
Fuel System Messages
FUEL LEVEL LOW
This message displays when your
vehicle is low on fuel. Refill the fuel
tank as soon as possible. See Fuel
Gauge on page 5‑11 andFilling the
Tank on page 9‑40 for more
information.
TIGHTEN GAS CAP
This message may be displayed if
the gas cap is not on, or is not fully
tightened. Check the gas cap to
ensure that it is on properly. See
Filling the Tank on page 9‑40 for
more information.

Black plate (7,1)Chevrolet Impala Owner Manual - 2012
Driving and Operating 9-7
Highway Hypnosis
Always be alert and pay attention to
your surroundings while driving.
If you become tired or sleepy, find a
safe place to park the vehicle
and rest.
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep the interior
temperature cool.
.Keep your eyes moving—scan
the road ahead and to the sides.
.Check the rearview mirror and
vehicle instruments often.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips for
driving in these conditions include:
.Keep the vehicle serviced and in
good shape.
.Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.Shift to a lower gear when going
down steep or long hills.
{WARNING
If you do not shift down, the
brakes could get so hot that they
would not work well. You would
then have poor braking or even
none going down a hill. You could
crash. Shift down to let the engine
assist the brakes on a steep
downhill slope.
{WARNING
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. The brakes will have
to do all the work of slowing down
and they could get so hot that
they would not work well. You
would then have poor braking or
even none going down a hill. You
could crash. Always have the
engine running and the vehicle in
gear when going downhill.
.Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
.Be alert on top of hills,
something could be in your lane
(stalled car, accident).

Black plate (9,1)Chevrolet Impala Owner Manual - 2012
Driving and Operating 9-9
WARNING (Continued)
If the vehicle is stuck in the snow:
.Clear away snow from around
the base of your vehicle,
especially any that is blocking
the exhaust pipe.
.Check again from time to
time to be sure snow does
not collect there.
.Open a window about 5 cm
(2 in) on the side of the
vehicle that is away from the
wind to bring in fresh air.
.Fully open the air outlets on
or under the instrument
panel.
.Adjust the climate control
system to a setting that
circulates the air inside the
vehicle and set the fan speed
to the highest setting. See
Climate Control System in the
Index.(Continued)
WARNING (Continued)
For more information about
carbon monoxide, see Engine
Exhaust on page 9‑24.
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 cannot 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 the
exhaust.
Run the engine for short periods
only as needed to keep warm, but
be careful. To save fuel, run the engine for only
short periods as needed to warm
the vehicle and then shut the engine
off and close the window most of
the way to save heat. Repeat this
until help arrives but only when you
feel really uncomfortable from the
cold. Moving about to keep warm
also helps.
If it takes some time for help to
arrive, now and then when you run
the engine, push the accelerator
pedal slightly so the engine runs
faster than the idle speed. This
keeps the battery charged to restart
the vehicle and to signal for help
with the headlamps. Do this as little
as possible to save fuel.

Black plate (19,1)Chevrolet Impala Owner Manual - 2012
Driving and Operating 9-19
not start and the key is held in
START, cranking will be stopped
after 15 seconds to prevent
cranking motor damage. To
prevent gear damage, this
system also prevents cranking if
the engine is already running.
Engine cranking can be stopped
by turning the ignition switch to
the ACC/ACCESSORY or
LOCK/OFF position.
When the Low Fuel warning
lamp is on and the FUEL LEVEL
LOW message is displayed in
the Driver Information Center
(DIC), the Computer‐Controlled
Cranking System is disabled to
prevent possible vehicle
component damage. When this
happens, hold the ignition switch
in the START position to
continue engine cranking.Notice:
Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after
5‐10 seconds, especially in very
cold weather (below −18°C or
0°F), it could be flooded with too
much gasoline. Try pushing the
accelerator pedal all the way to
the floor and holding it there as
you hold the key in START for
up to a maximum of 15 seconds.
Wait at least 15 seconds
between each try, to allow the
cranking motor to cool down.
When the engine starts, let go of
the key and accelerator. If the
vehicle starts briefly but then
stops again, repeat these steps. This clears the extra gasoline
from the engine. Do not race the
engine immediately after starting
it. Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical parts
or accessories, you could change
the way the engine operates.
Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty.

Black plate (29,1)Chevrolet Impala Owner Manual - 2012
Driving and Operating 9-29
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑20. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.