1993 GMC SIERRA check engine

As in any driving situation, keep pace with traffic and allow adequat\
e
following distances.
Hill and Mountain Roads
I r
AM470001
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” in the Index for information about driving off-road.)
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.
Know how to go down hills. The most important thing to know is this: let
your engine do some
of the slowing down. Don’t make your brakes do it
all. Shift to a lower gear when you go down a steep or long hill. That
way, you will slow down without excessive use of your brakes.
If you don’t shift down,’ your brakes could get so hot that they
- b wouldn’t work well. You would then have poor braking or even none
going
down a hill. You could crash. .Shift down to let your engine
assist your brakes on a steep downhill slope. I I
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Your Driving and the Road
If You’re Caught in a Blizzard
AM48002
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 sur\
e that you are near help and you can hike through the snow. Here are some t\
hings
to do to
summon help and keep yourself and your passengers safe: Turn o\
n your
hazard flashers. Tie a red cloth to your vehicle to alert pol\
ice that you’ve
been stopped by the snow. Put on extra clothing or wrap a bl\
anket around
you. If you have no blankets or extra clothing, make body ins\
ulators 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,
I 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
I from the wind. This will help keep CO out. I
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Your Driving and the Road
drivers behind you are seeing your signal when they are not. It’s important to
check occasionally to be sure the trailer bulbs are still working.
Driving on Grades
Reduce speed and shift to a lower gear before you start down long or steep
downgrade.
If you don’t shift down, you might have to use your brakes so
much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to
45 mph (70
kmlh) or less to reduce the possibility of engine and transmission overheating.
IT you have an automatic transmission, you should use D (or, as you need to,
a lower gear) when towing a trailer. Operating your vehicle i\
n
D when towing
a trailer will minimize heat buildup and extend the life of your transmission.
Or, if you have a manual transmission with fifth gear and you are towing a
trailer, it’s better not to use fifth gear. Just drive in fourth gear
(or, as you
need to, a lower gear).
Parking on Hills
You really should not park your vehicle, with a trailer attached, \
on a hill. If
something goes wrong, your rig could start to move. People can\
be injured
and both your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s how to do it:
1. Apply your regular brakes, but don’t shift into P (Park) yet, or into gear
2. Have someone place chocks under the trailer wheels.
for a manual transmission.
3. When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking brake, and \
then
5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a
6. Release the regular brakes.
shift
to
P (Park), or R (Reverse) for a manual transmission.
drive gear-not in
N (Neutral).
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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 suddenl\
y.
You
or others could be injured. To be sure your vehicle won’t move,
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 Parklng on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine;
Shift into a gear; and
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 To wing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are esp\
ecially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. 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.
mailer Wiring Harness
See “Trailer Wiring Harness’’ in the Index.
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.
To turn off the flasher, pull out on the collar.
When the hazard warning flashers are on, your turn signals won’t work.
Other Warning Devices
If you carry reflective triangles, you can set one up at the side of the road
about
300 feet (100 m) behind your vehicle.
Jump Starting
If your battery (or batteries) has run down, you may want to use another
vehicle and some jumper cables to start your vehicle. But please follow the
steps- below
to do it safely.
CAUTION
Batteries can hurt you. They can be dangerous because: I
They contain acid that can burn you.
They contain gas that can explode c te. ..
They contain enough electricity to burn you.
n hurt you. I
If you don’t follow these ’ !ps exactly, some or all of tt- --e things
-I
To Jump Start Your Vehicle ’
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
If the other system isn’t a 12-volt system with a negative ground, bot
I 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
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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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I
I
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LL
1
PO593
The coolant level should be at or above the COLD mark. If it isn’t, you may
have a leak in the radiator hoses, heater hoses, radiator, water pump or
somewhere else in the cooling system.
Heater and radiator hoses, and other engine parts, can be very\
hot.
-, Don’t touch them. If you do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, it cou
lose all coolant. That could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the vehicle.
I I
NOTICE
Engine damage from running your engine without coolant isn’t covered by
I your warranty.
If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running.
If the engine is overheating, the fan should be running.
If it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
If it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
COLD, add a 50hO mixture of clean water (preferably distilled) and a proper
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Service & Appearance Care
.....
Here you will find information about the care of your vehicle . This Section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information about
your vehicle. and a section devoted to its appearance care
.
Service ........................................................................\
........................................... 6-3
Fuel (Gasoline Engines)
........................................................................\
............... 6-4
Diesel Fuel Requirements and Fuel System
...................................................... 6-6
Checking Things Under the Hood
..................................................................... 6-17
Hood Release
........................................................................\
.......................... 6-18
Cleaning Your Diesel Engine
........................................................................\
.. 6-19
Noise Control System
........................................................................\
............. 6-19
Engine Oil (Except Diesel)
........................................................................\
..... 6.20
Engine Oil (Diesel Engines)
........................................................................\
... 6-26
Air Cleaner
........................................................................\
............................... 6-31
Automatic Transmission Fluid
........................................................................\
. 6-33
Manual Transmission Fluid
........................................................................\
..... 6-36
Hydraulic Clutch
........................................................................\
....................... 6-37
Transfer Case
........................................................................\
.......................... 6-39
Front Axle ........................................................................\
................................. 6-40
Rear Axle
........................................................................\
................................. 6-41
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