1998 GMC SIERRA open hood

Engine Coolant Heater (If Equipped)
In very cold weather, 0°F (- 1 SOC) or colder, the engine
coolant heater can help. You’ll get easier starting and
better fuel economy during engine warm-up. Usually,
the coolant heater should be plugged in a minimum of
four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
The engine coolant heater electrical cord
is located
on the driver’s side
of the engine compartment, near
the power steering reservoir.
3. Plug it into a normal, grounded 110-volt AC outlet.
Plugging the cord into an ungrounded outlet
could cause an electrical shock.
Also, the wrong
kind
of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three-prong 110-volt
AC outlet. If the cord won’t reach, use a
heavy-duty three-prong extension cord rated for
at least
15 amps.
4. Before starting the engine, be sure to unplug and store
the cord
as it was before to keep it away from moving
engine parts.
If you don‘t, it could be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of
oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer
in the area where you‘ll be parking your
vehicle. The dealer can give
you the best advice for that
particular area.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles 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.
To avoid the possibility
of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in
PARK (P) or a manual transmission
in NEUTRAL (N).
If you have a four-wheel-drive
vehicle, be sure the transfer case is not in
NEUTRAL
(N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off all lamps
that aren’t needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
I 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.
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools
away from
any underhood electric fan.
5-4
t
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If Steam Is Coming From Your Engine
I
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine
if you see or hear steam coming
from it. Just turn
it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
CAUTION: (Continued)
I
If you keep driving when your engine is
overheated, the liquids in
it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out
of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.
If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little
too hot when you:
0 Climb a long hill on a hot day.
0 Stop after high-speed driving.
0 Idle for long periods in traffic.
0 Tow a trailer. See “Driving on Grades” in the Index.
5-14
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If you get the overheat warning with no sign of steam,
try this for
a minute or so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (@)
for automatic transmissions.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign
of steam, push the accelerator until
the engine speed
is about twice as fdst as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes. Now see if the warning stops.
But then, if you still have the warning, turn ofthe
engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
Cooling System -- Gasoline Engines
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan(s)
5-15
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Be sure the posted octane is at least 87. If the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don’t worry if you hear a little pinging noise when
you’re accelerating or driving
up a hill. That’s norlnal,
and you don’t have to
buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications.
If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission control system
performance may be affected. The malfunction indicator lamp
on your instrument
panel may turn on and/or your
vehicle may fail
a smog-check test. If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause
of’ fdilure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does not recommend the
use
of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator
lamp on your instrument panel
may
turn on. If this occurs, return to your authorized
GM dealer for service.
6-4
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Hood Release
To open the hood, first
pull the handle inside
the vehicle.
Then
go to the front of the vehicle and pull up on the
secondary hood release, located just to the passenger’s
side of the center
of the grill.
Lift the hood.
Before closing the hood, be sure all filler caps
are on
properly. Pull down the hood and close it firmly.
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Tachometer .................................. 2-63
Voltmeter
................................... 2-67
Garage Door Opener
............................ 2-5 1
GAWR ....................................... 4-43
Gear Positions. Automatic Transmission
............. 2- 15
Gear Positions. Manual Transmission .......... 2- I8 . 2- 19
GloveBox .................................... 2-51
Gross Axle Weight Rating ........................ 4-43
Gross Vehicle Weight Rating
...................... 4-43
Guide en Franpis
11
GVWR ....................................... 4-43
.. .................................
Halogen Bulbs ................................ 6-39
Hazard Warning Flashers
.......................... 5-2
Head Restraints ................................. 1-5
Headlamps .................................... 2-41
Bulb Replacement
....................... 6-40. 6.4 I
High/Low Beam Changer ...................... 2-36
On Reminder
................................ 2-42
Wiring
..................................... 6-71
Heating
........................................ 3-5
High-Beam Headlamps
.......................... 2-36
Hill and Mountain Roads
......................... 4-34
Hitches. Trailer
................................. 4-55
Hood
Checking Things Under ......................... 6-9
Release
..................................... 6-10
Horn ......................................... 2-34
Hydraulic Clutch Fluid
...................... 6-25 . 7-46
Hydraulic Clutch System Check
................... 7-41
Hydroplaning
.................................. 4-30
Hearing Ilnpaired
. Customer Assistance .............. 8-4
Highway Hypnosis
.............................. 4-33 Ignition
Positions
..............................
Brakesystem ................................ 7-45
Drive Axle
.................................. 7-45
Engine Cooling System
........................ 7-44
Exhaust
Systems ............................. 7-44
Steering
.................................... 7-44
Suspension
.................................. 7-44
Throttle Linkage
.............................. 7-44
Transfer Case (Four-Wheel Drive)
............... 7-45
Instrument Panel
............................... 2-60
Cleaning
.................................... 6-64
Cluster
..................................... 2-62
FuseBlock
.................................. 6-72
Intensity Control
............................. 2-43
Interior Lamps
................................. 2-43
.................................... J ack. Tire 5-25
Jump Starting
................................... 5-3
Key Lock Cylinders Service
..................... 7-41
Key Release Button
............................. 2-12
Keyless Entry System ............................ 2-6
Keys
.......................................... 2-2
9-5
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