1996 GMC SIERRA engine

ANTI -
LOCK
Qnti-Lock Brake System Warning Light
With the anti-lock brake.
system, this light will come
on when
you start your
engine and may stay on
for several seconds.
That’s normal.
If the light stays on, or comes on when 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 regular 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” earlier
in this part.
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.
Engine Coolant Temperature Gage
I This gage shows the engine
~ coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F
(100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260°F ( 125 “C) mark. If the
gage reaches the 260°F
(I 25 “C) mark, it indicates that
the cooling system is working beyond its capacity.
In “Problems
on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
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Malfunction Indicator Lamp (Service
- ;ine Soon Light) (Gasoline Engine)
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission SERVICE
ENGINE
SOON
control systems.
This system
is called OBD I1 (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. (In Canada,
OBD TI is replaced by
Enhanced Diagnostics.) The
SERVICE ENGINE SOON
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, which
may prevent more serious damage to your vehicle. This
system is
also designed to assist your service technician
in correctly diagnosing any malfunction.
I 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.
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:
0 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
is required.
0 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.
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If the Light Is Flashing If the Light Is On Steady
The following may prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
0 If 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 “If
the Light
Is On Steady” following.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Put your vehicle in PARK (P). Turn the
key off, wait at least
10 seconds and restart the engine.
If the light remains
on steady, see “If the Light Is On
Steady” following.
If the light is still flashing follow the
previous steps, and drive the vehicle
to your dealer or
qualified service center for service.
You may be able to correct the emission system
malfunction by considering the following:
Did you just put fuel
into your vehicle?
If so7 reinstall the fuel cap, making sure to fully install
the cap. The diagnostic system can determine if the fuel
cap has been left off or improperly installed. This will
allow fuel to evaporate into
the atmosphere. A few
driving trips 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. it
will take a few driving trips to turn the light off.
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Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel (see
"Fuel" 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, hesitaIion 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 this condition, 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.
Oil Pressure Gage
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The oil pressure gage shows
the engine oil pressure in psi
(pounds per square inch)
when the engine is running.
Canadian vehicles indicate pressure in
Wa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and
oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused
by a dangerously low oil level or some other problem
causing low oil pressure. Check your
oil as soon
as possible.
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/A CAUTION: l!,L- .
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.
I NOTICE:
Damage to your engine from neglected oil
problems can be costly and
is not covered by your
warranty.
Shift Light
SHIFT
This light is used on some
models
with manual
transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See “Shift Light” or “Shift Speeds”
in this
section for more information.
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Daytime Running Lamps Indicator Light Check Gages Light
This light goes on whenever
the DRL are on.
CHECK
GAGES
This light will come on
briefly when you are
starting
the engine.
When
it begins to get dark, the DRL indicator light is a
reminder to turn
on your headlamps.
If the light comes on and stays on w.hile you are driving,
it could indicate a problem with your vehicle. It could be
a problem with your oil pressure, coolant temperature,
or some other problem. Check your various gages to see
if they are in the warning zones. If they are, have your
vehicle serviced right away.
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Fuel Gage
81 The fuel gage, when the
ignition is on, tells you
about how much fuel you
have left
in your tank.
E
The gage will first indicate EMPTY (E) before you
are
out of fuel, and you should get more fuel as soon
as possible. Here
are four situations
you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before the
gage reads
FULL (F).
It takes a little more or less fuel to fill up than the
fuel gage indicated.
For example, the gage may have
indicated the tank was half full, but
it actually took a
little more or less than half the tank’s capacity to fill
the tank.
The gage moves a little when you turn a corner or
speed up.
The gage doesn’t go back to EMPTY (E) when you
turn off the ignition.
If you have a diesel engine, see “Fuel Gage”
in the
Diesel Engine Supplement.
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The A/C button, between the temperature and mode
knobs, allows
the air coming into your vehicle to be
cooled. This setting
is useful for normal cooling on hot
days. When
you use A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches a comfortable interior temperature.
With the
A/C on, move the temperature knob to MAX
for maximum cooling.
This setting also puts the system
in the recirculation mode and helps
to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also cools the air the fastest. After
the vehicle’s interior reaches a comfortable temperature,
move the temperature knob clockwise to place the air
conditioning system
in the normal mode.
Heating
The heater works best if you keep your windows closed
while using
it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in the
red area.
If you use the engine coolant heater before starting your
engine (in cold weather (20°F (-8°C) or lower), your
heating system
will produce warmer air faster, to heat
the passenger compartment
in cold weather. The
use
of an engine coolant heater also reduces the
time
it takes for the engine to reach normal operating
temperature, and shortens the time
it takes the heater to
reach full output. For more information, see “Engine
Coolant Heater”
in the Index.
Ventilation System
For mild outside temperature when little heating or
cooling
is needed, use VENT to direct outside air
through
your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation systeril supplies outside air
to the inside of your vehicle when it is moving. With
the side windows closed, air will flow into the front
air inlet grilles, through the vehicle, and out the air
exhaust valves.
Outside air will
also enter the vehicle when the heater or
the air conditioning fan is running, unless you have
the
recirculation button pushed in. For more information on
the recirculation button, see “Air Conditioning” earlier
in this section.
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