1994 GMC SIERRA check engine

Heater Output
Engine Coolant Heater (Engine Block Heater)
If your vehicle has a diesel engine, it is equipped with an engine coolant
heater. An engine coolant heater
is optional on gas engine vehicles. You can
use an engine coolant heater during initial start-up
in cold weather (20” F,
-8” C, or lower) to help heat the passenger compartment faster. Because an
engine coolant heater warms the engine coolant, your vehicle’s heating
system can provide some heat
as soon as you start the engine.
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.
Diesel Engine
If you idle your diesel engine for a long time when it’s cold outside, your
heater may blow out cool air. This
is normal. When you increase the engine
speed, your heater should blow
out warmer air. If it doesn’t, your coolant
level may be low. See “Engine Coolant”
in the Index to find out how to
check your coolant level.
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FM Stereo
FM stereo will give you the best sound. But FM signals can only reach
about
10 to 40 miles (16 to 65 km). And, tall buildings or hills can interfere
with
FM signals, causing the sound to come and go.
AM
The range for most AM stations is greater than for FM, especially at night.
The longer range, however, can cause stations to interfere
with each other.
AM
can pick up noise from things like electrical storms and power lines. If
the noise interferes with your listening, try reducing the treble to lessen the
noise.
AM Stereo
This means the Delco@ system can receive C-QUAM@ stereo broadcasts.
Many AM stations around
the country use C-QUAM@ to produce stereo,
though some
do not. If your Delco@ system can get C-QUAM@, your
“STEREO” light will come on when you’re receiving it. (C-QUAM’ is a
registered trademark of Motorola, Inc.).
NOTICE:
Before you add any sound equipment to your vehicle - like a
tape player, CB radio, mobile telephone or two-way radio - be
sure you can add what you want. If you can,
it’s very important
to do it properly. Added sound equipment may interfere with the
operation
of your vehicle’s engine, Delco@ radio or other
systems, and even damage them. And, your vehicle’s systems
may interfere with the operation of sound equipment that has
been added improperly.
So, before adding sound equipment, check with your dealer and
be sure to check Federal rules covering mobile radio and
telephone units.
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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.
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 Vehicle
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
inside and outside?
Wiper Blades: Are they in good shape‘?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
0 Lights: Are they all working? Are the lenses clean‘?
0 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‘?
0 Weather Forecasts: What’s the weather outlook along your route?
Should you delay your trip
a short time to avoid a major storm system?
0 Maps: Do you have up-to-date maps?
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 same 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.
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What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 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 mirrors and your instruments frequently.
0 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.
Hill and Mountain Roads
Driving on steep hills or mountains is different from driving in flat or
rolling terrain.
If you drive regularly in steep country, or if you're planning to visit there,
here are some tips that can make your trips safer and more enjoyable. (See
"Off-Road Driving" in the Index for information about driving off-road.)
0 Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can work
hard
on mountain roads.
0 Know how to go down hills. The most important thing to know is this:
let your engine do some of the slowing down. Shift to a lower gear
when you go down
a steep or long hill.
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If You’re Caught in a Blizzard
If you are stopped by heavy snow, you could be in a serious situation. You
should probably stay with your vehicle unless you know for sure that you
are near help and you can hike through the snow. Here are some things
to do
to summon help and keep yourself and your passengers safe: Turn on your
hazard flashers. 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.
A 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.
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A CAUTION:
It can be dangerous to get out of your vehicle if the shift lever is
not fully in “P” (Park) with the parking brake firmly set. Your
vehicle can roll.
If’ you have left the engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle
won’t move, even when you’re on fairly level ground, use the
steps that follow.
If you have four-wheel drive and your transfer case is in “N”
(Neutral), your vehicle will be free to roll, even if your shift lever
is in
“P” (Park). So, be sure the transfer case is in a drive gear
- not in “N” (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking
On Hills” in the Index.
When You Are Ready to Leave After Parking on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine;
Shift into a gear; and
0 Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important in trailer operation are automatic
fluid (don’t overfill), engine oil,
axle lubricant, belts, cooling system, and brake adjustment. Each of these
is
covered in this manual, and the Index will help you find them quickly. If
you’re trailering, it’s
a good idea to review these sections before you start
your trip.
Check periodically to see that all hitch nuts and bolts are tight.
Trailer Light Wiring
See “Trailer Wiring Harness” in the Index.
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To Jump Start Your Vehicle
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
I NOTICE:
If the other system isn’t a 12-volt system with a negative
ground, both vehicles can be damaged.
If you have a diesel engine vehicle with two batteries (or more), you
should know before
you begin that, especially in cold weather, you may
not be able to get enough power from
a single battery in another
vehicle to start your diesel engine.
If your vehicle
has more than one battery, use the battery that’s on the
passenger side
of the vehicle - this will reduce electrical resistance.
sure the vehicle’s aren’t touching each other.
If they are, it could cause
a ground connection you don’t want. You wouldn’t be able to start your
vehicle, and the bad grounding could damage
the electrical systems.
You could be injured
if the vehicles roll. Set the parking brake firmly
on each vehicle. Put an automatic transmission
in “P” (Park) or a
manual transmission in “N” (Neutral). If you have a four-wheel-drive
vehicle, be sure
the transfer case is not in “N” (Neutral).
2. Get the vehicles
close enough
so the jumper cables can reach, but be
3. Turn off the ignition on both vehicles. Turn off all lights that aren’t
needed, and radios. This will avoid sparks and help save both batteries.
And it could save
your radio!
NOTICE:
If you leave your radio on, it could be badly damaged. The
repairs wouldn’t be covered by your warranty.
4. Open the hoods and locate the batteries. Find the positive (+) and
negative
(-) terminals on each battery.
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5. Check that the jumper cables don't have loose or missing insulation. 'Ir'
they do, you could get a shock. The vehicles could be damaged, too.
Before
you connect the cables, here are some basic things you should
know. Positive
(+) will go to positive (+) and negative (-) will go to
negative
(-) or a metal engine part. Don't connect (+) to (-) or you'll
get a short that would damage the battery and maybe other parts, too.
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