1998 GMC SIERRA check engine

5. If you have a four-wheel-drive vehicle,
be sure the transfer case is in
a drive gear and not
in
NEUTRAL (N).
6. Release the regular brakes.
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/r CAUTIOIA:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in
PARK (P) 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
NEUTRAL (N), your vehicle will be free
to
roll, even if your shift lever is in PARK (P). So,
be sure the transfer case is in a drive gear -- not
in
NEUTRAL (N).
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
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 transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, 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.
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I
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 flashlight
if
you need more light.
Be sure the batteries have enough water. You
don’t need to add water to the ACDelco
Freedom@ battery (or batteries) installed 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.
Battery fluid contains acid that can burn you.
Don’t get it on you.
If you accidentally get it in
your eyes or on your skin, flush the place 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
basic things
you should know. Positive (+) will
go to positive
(+) and negative (-) will go to a
metal engine part. Don’t connect positive
(+) to
negative
(-) or you’ll get a short that would
damage the battery and maybe other parts
too.
On vehicles equipped with dual batteries, make any
battery connections
to the primary battery located on
the passenger’s side of the vehicle.
Fans or other moving engine parts can injure you
badly. Keep your hands
away from moving parts
once the engine is running.
5-5
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Section 6 Service and 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 part devoted to its appearance care.
6-2
6-3
6-5
6-6
6- 8
6-9
6- 13
6- 14
6-18
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6-24
6- 25
6-26
6-26
6-28 6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries (Gasoline Engines)
Filling Your Tank (Gasoline Engine)
Filling a Portable Fuel Container
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engine)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat
, 6-33
6-3 3
6-35
6-39
6-39
6-50
6-5
1
6-6 1
6-62
6-65 6-69
6-70
6-70
' 6-76
6-77 6-79 Power
Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Electrical System Replacement
Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
6-1
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-
/! CAUTION:
You can be injured and your vehicle could be
damaged
if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts and tools before you attempt
any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off.
You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around
it. This may cause wind noise
and affect windshield washer performance. Check
with
your dealer before adding equipment to the outside of
your vehicle.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System”
in the Diesel Engine
Supplement. For vehicles with gasoline engines, please.
read this.
Use regular unleaded gasoline rated at
87 octane or higher.
At
a minimum, it should meet specifications ASTM D48 14
in the United States and CGSB 3.5-M93 in Canada.
Improved gasoline specifications have been developed
by
the American Automobile Manufxturers Association
(AAMA) for better vehicle performance and engine
protection. Gasolines meeting the
AAMA specification
could provide improved chiveability and emission control
system protection compared to other gasolines.
6-3
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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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To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming
in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should
not have to add
anything to the fuel.
In addition, gasolines containing
oxygenates, such as ethers and ethanol, and
reformulated gasolines may be available
in your area to
help clean the air. General Motors recommends that
you
use these gasolines if they comply with the
specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use
it. It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t
be covered under your warranty.
Fuels in Foreign COUI
(Gasoline Engines)
If you plan on driving in another country outside the
United States
or Canada, the proper fuel may be hard to
find. Never use leaded gasoline or any other fuel not
recommended
in the previous text on fuel. Costly repairs
caused by use of improper fuel wouldn’t be covered by
your warranty.
To check on fuel availability, ask an auto club, or
contact
a major oil company that does business in the
country where you’ll be driving.
You can also write us at the following address for
advice. Just tell us where you’re going and give your
Vehicle Identification Number
(VIN).
General Motors Overseas Distribution Corporation
1908 Colonel Sam Drive
Oshawa. Ontario
L 1 H 8P7
6-5
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Checking Things Under the Hood
I I A CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
I
A CAUTION:
I
I
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline or
diesel fuel, oil, coolant, brake fluid, windshield
washer and other fluids, and plastic or rubber.
You or others could be burned. Be careful not
to drop or spill things that
will burn onto a
hot engine.
6-9
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Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see “Engine Oil
(Diesel Engine)” in the Diesel Engine Supplement.
It’s
a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the
oil must
be warm and the vehicle
must be on level ground.
.. ..
The engine oil dipstick has a yellow ring handle and is
located
on the passenger’s side of the engine.
Turn
off the engine and give the oil a few minutes to
drain back into
the oil pan. If you don’t, the oil dipstick
might not show the actual
level.
Checking Engine Oil
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
u
6-14
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