1993 GMC SIERRA check engine light

. If the light. doesn’t go off, wait a few seconds, then try staiting your engine
again. And, see your dealer
as soon as you- can for a starting system check.
If the light comes on and then goes out and you know your batte\
ries are
charged, but your engine still won’t start, your vehicle nee\
ds service.
If your batteries don’t have enough .charge to start ,your engine, see “Battery”
in the Index.
Be sure you have the right oil for your engine, and that you’ve changed the
oil
at the proper times. If you use the wrong oil, your engine may be harder
to start.
If the engine starts, runs a short time, then stops, your vehicle needs service.
NOTICE
Don’t use starting “aids” such as ether or gasoline, in the m~v intakc They
could damage your engine.
..- - .- * K2214
In very cold weather, 0°F (-18°C) or colder, if you have an engine block
heater, it can help. You’ll get easier starting and better fuel economy during
engine warm-up.
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Features & Controls
“Engine Coolant’’ in the Index and have your vehicle s\
erviced as soon as
you can.
Charging System Light
K2328
The red charging system light is located at the upper right hand corner of
your instrument cluster. It should come on briefly when you turn on the
ignition, before starting the engine, as a check to show you it is working.
After the engine starts, the light should
go out. If it stays on, or comes on
while you are driving, you may have a problem with your elect\
rical charging system. It could indicate that you have a loose alternator drive belt, or\
that
you have some other 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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Malfunction Indicator Lamp (Service Engine Soon Light)
I
SERVICE
EF_'31NE
SOON
K2329
A computer monitors operation of your fuel, ignition, and emission control
systems. This light should come on when the ignition is on bu\
t the engine is not running, as a check to show you it is working. If it does not come on at
all, have it fixed right away.
If it stays on, or comes on while you are driving,
the computer is indicating that you have a problem. You should take your
vehicle in for service soon.
NOTICE
E
If you keep driving your vehicle with this light on, after awhile the emission
controls won't work well, your fuel economy won't be as good, and your
engine may not run as smoothly. This could lead
to costly repairs not
covered by your warranty.
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Features & Controls
CHECK GAGES Light
This light will come on briefly when you are starting the engine. If the light
comes on and stays
on while you are driving, it could indicate a problem with
your vehicle. Check your various gages to see
if they are in the warning
zones.
K2330
Daytime Running Lights (DRL) Indicator Light (Canada On/y)
I-
K2318
If your vehicle was first sold, when new, in Canada, you will have this green
light on the instrument panel. It will light, just above the \
speedometer,
whenever the Daytime Running Lights are on. For more details a\
bout DRL,
see “Headlights and Vehicle Lighting” in this section.
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close behind you, you can allow a little extra time and flash\
your brake lights (in addition to your turn signal) as extra warning that you are about to slow
down and exit.
The exit ramp can be curvea, somerlmes quite sharply. The exit\
speed is
usually posted. Reduce your speed according to your speedometer,\
not to
your sense of motion. After driving for any distance at higher\
speeds, you
may tend to think you are going slower than you actually are.\
For example,
40 rnph (65 km/h) might seem like only 20 mph (30 km/h). Obviously, this
could lead to serious trouble
on a ramp designed for 20 mph (30 kmlh)!
Driving a Long Distance
Although most long trips today are made on freeways, there are\
still many
made on regular highways.
Long-distance driving on freeways and regular highways is the s\
ame in some
ways. The trip has to be planned and the vehicle prepared, you drive at\

higher-than-city speeds, and there are longer turns behind the \
wheel. You’ll
enjoy your trip more
if you and your vehicle are in good shape. Here are
some tips for a successful long trip.
Before Leaving on a Long Trip
Make sure you’re ready. Try to be well rested. If you must start when you’re
not fresh-such as after a day’s work-don’t plan to make too many miles
that first part of the journey. Wear comfortable clothing and \
shoes you can easily drive in.
Is your vehicle ready for a long trip? If you keep it serviced and maintained,
it’s ready to go.
If it needs service, have it done before starting out. Of
course, you’ll find experienced and able service experts in \
your vehicle’s
dealerships all across North America. They’ll be ready and willing to help \
if
you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid: Is the reservoir full? Are all windows clean
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
Lights: Are they all working? Are the lenses clean?
Tires: They are vitally important to a safe, trouble-free trip. Is the tread
good enough for long distance driving? Are the tires all inflated to the
recommended pressure? inside and outside?
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‘
Your Driving and the Road
Weather Forecasts: What’s the weather outlook along your route?
Should -you delay your trip a short time to avoid a major storm system?
Maps: Do you have up-to-date maps? . .. .. . -1 .. On fhe Road
Unless you are the only driver, ‘it is good .to share the driving task’with
others. Limit turns behind the wheel to about
100 miles (160 km) or two
hours at a sitting. Then, either change drivers or stop for s\
ome- refreshment
like coffee, tea or soft drinks and some limbering up. But do\
stop and move
around. Eat lightly along the way. Heavier meals tend
to make some people
sleepy.
.. . .- , - .~
On two-lane highways or undivided multilane highways that do no\
t have
controlled access, you’ll want to watch for some situations \
not usually found
on freeways. Examples are: stop signs and signals, shopping cen\
ters with
direct access to the highway, no passing zones and school zone\
s, vehicles
turning’ left and right
off the road, pedestrians, cyclists, parked vehicles, and
even animals.
Highway Hypnosis
Is there actually such a condition as “highway hypnosis?” Or \
is it just plain ,
falling asleep at the wheel? Call it highway hypnosis, lack of awareness, or
whatever.
’ There is something about an easy stretch of road with the sam\
e scenery,
along with the hum
of the tires on the road, the drone of the engine, and the
, rush of the wind against the vehicle that can make you sleepy\
. Don’t let it ’.
happen to you! If it does, your vehicle can leave the road in less than a
second,
and you could crash and be injured.
What can you do about highway hypnosis? First, be aware that it
can
happen.
Then here are some tips:
Make sure your vehicle is well - ventilated, with a comfortably cool interior.
Keep your eyes moving. Scan the road ahead and to the sides. \
Check
your rearview mirrors frequently and your instruments from time \
to time.
This can help you avoid a fixed stare.
-
,x ! - : ,-.:.&---z-.- ..* .-7
0 d
Wear good sunglasses in bright light. Glare can cause drowsiness. But
don’t wear sunglasses at night. They will drastically reduce \
your overall
-%
vision at the very time you need all the s.eeing power you h\
ave.
If you get sleepy, pull off the road into a rest, service, or parking area
and take a nap, get some exercise, or both. For safety, treat\
drowsiness
on the highway as an emergency.
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IA
Using a match near a battery can cause battery gas to explode.
People have been hurt
doing this, and some have been blinded. Use
a flashiight if you need more light.
Be sure the batteries have enough water. You-don? need
to adb
water to the Delco Freedom* battery (or batteries) instailed in every
new
GM vehicle. But if a battery has filler caps, be sure the right
amount of fluid
is there. If it is low, add water to take care of that
first.
If you don’t, explosive gas could be present. .hr~ic;. -- ,
Battery fluid conbins acid that can burn you. Don’t. get it. on you.
. you accidentally get it in your eyes or on your skin, ftush the placl
~~~~-,~~~~.~-:~~.~.~. -2-
.with water and get medical help immediately.
5. Check that the jumper cables don’t have loose or missing insulation. If
they do, you could get a shock. The vehicles could be damaged, too.
Before you connect the cables, here are some things you should\
know.
Positive
(t) will go to positive (t) and negative (-) will go to negative
(-) or a metal engine part. Don’t connect (t) to (-) or you’ll get a
short that would damage the battery and maybe other parts, too\
.
I
Fans or other moving engine parts can injure you badly. Keep your
hands away from moving parts once the engines are running.
6. Connect the red positive (t) cable to the positive (t) terminal of the
vehicle with the dead battery. Use a remote positive
(t) terminal if the
vehicle has one.
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Service & Appearance Care
Diesel Fuel Requirements
and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you
to buy permits or pay special taxes.
Some of these restrictions apply only
to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions in any state or province, contact your auto club, \
the police or
other officials.
Fuel Requirements
1 NOTICE
Diesel fuel or fuel additives not recommended in this manual could
damage your fuel system and engine. Your warranty wouldn’t cover thi
damage. And:
Diesel fuel that has been mixed with engine oil could damage your
engine and emission controls.
Always check with your service station
his
diesel fuel, it can be difficult to restart your
engine. “Running Out of Fuel,” later
in this section, tells you how to
get
it started again. To avoid all this, try never to let. your tank get
What Fuel to Use:
You can use either Number I-D or Number 2-D diesel fuel, but you’ll get
better fuel economy using
2-D.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle
to shut off, even though your tank isn’t full. If this happens, just
wait for the foaming to stop and then continue to fill your tank.
1 CAUTION
- Heat coming from the engine may cause the fuel to expand and force
the fuel out of your tank. If something ignites the fuel, a \
fire could start
and people could be burned.
To help avoid this, fill your fuel tank only
until the automatic nozzle shuts
off. Don’t try to “top if off .” I
I
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