1997 GMC SIERRA check engine

Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even if the bulbs
on the trailer
are burned out. Thus, you may think 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 a 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 around 45 mph (70 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC OVERDRIVE (a). You
may want to
shift the transmission to THIRD
(3) or, if necessary, a
lower gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If you have a manual transmission and you are towing a
trailer, it’s better not to use
FIFTH (5) gear. Just drive in
FOURTH
(4) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If
you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating.
To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in
PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine
off.
If you do get the overheat warning, see “Engine
Overheating”
in the Index.
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When You Are Ready to Leave After
Parkine
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.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle, between
the frame rails. An electrical
connector will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap
it to your vehicle’s frame
rail. Be sure you leave it loose enough
so the wiring
won’t bind or break when turning with the trailer, but
not
so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow
a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You
should select a trailer with a CHMSL on it or, if one is
not available, have one installed. See your
GM dealer
about how to connect your vehicle’s wiring
to a
trailer CHMSL.
Check periodically to see that all hitch nuts and bolts
are tight.
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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 Delco 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.
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 negative (-)
or 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.
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engines are running.
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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.
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6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries - - Gasoline
Engines
Filling Your Tank
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engines)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat 6-33
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6-49 6-50
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6-60
6-64
6-68
6-69
6-70 6-75
6-76
6-78 Power Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade
R
Tires
Appearance Care .eplacement
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 Specifications
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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 GM 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 D4814 in the United States and CGSB
3.5-M93
in Canada. Improved gasoline specifications have been
developed by
the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting
the AAMA
specification could provide improved driveability and
emission control system protection compared to
other gasolines. 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
still 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 normal,
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 tune-up 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 andor your vehicle
may fail a smog-check test. If this occurs, return
to your
authorized GM dealer for diagnosis
to determine the
cause of failure. 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.
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Some gasolines that are not reformulated for low
emissions contain
an octane-enhancing additive called
methylcyclopentadlenyl manganese tricarbonyl
(MMT);
ask your service station operator whether or not his fuel
contains
"T. 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.
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
NOTICE: (Continued)
I NOTICE: (Continued) I
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 Countries -- 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 International Product Center 1908 Colonel Sam Drive
Oshawa, Ontario
L 1 H 8P7
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Checking Things Under the Hood
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.
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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.
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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.
When to Add Oil
If the oil is at or below the ADD mark, then you’ll need
to add at least one
quart of oil. But you must use the
right kind. This part explains what kind of oil to use.
For
crankcase capacity, see “Capacities and Specifications”
in the Index.
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