1996 GMC SIERRA check engine

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while
you:
0 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 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.
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.
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A CAUTION:
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.
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
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.
1 things you should know. Positive (+) will go to
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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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 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 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.
In Canada. some gasolines contain an octane-enhancing
additive called
MMT. If you use such fuels, your
emission control system performance may deteriorate
and the tnalfunction indicator lamp
on your instrument
panel may turn on. If this happens, return to your
authorized
CM dealer for service.
To provide cleaner air, all gasolines 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.
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Fuels in Fo ign 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 Overseas Distribution Corporation,
North American
Export Sales (NAES)
1908 Colonel Sam Drive
Oshawa, Ontario
L 1 H 8P7
Filling Your Tank
The fuel cap is behind a
hinged door on the left side
of your vehicle.
On a chassis-cab model, refuel the front
tank first, or in
instances when only a partial fuel fill is desired.
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Be careful not to spill gasoline. Clean gasoline from
painted surfxes as soon
as possible. See “Cleaning the
Outside
of Your Vehicle” in the Index.
When you put the cap back
on, turn it to the right until
you hear at least three clicks. Make sure you fully install
the cap. The diagnostic system can determine if the fuel
cap has been
left off or improperly installed. This would
allow
fuel to evaporate into the atmosphere. See
“Malfunction Indicator Lamp” in the Index.
I NOTICE:
If you need a new cap, be sure to get the right
type. Your dealer can get one for you. If you get
the wrong type, it may not fit or have proper
venting, and your fuel tank and emissions system
might be damaged.
Checking Things Under the Hood
h
I ! CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
hjure you even when the engine
is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
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. 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.
The engine oil dipstick has a yellow ring handle and is
located on the passenger side
of the engine.
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The air cleaner assembly
has an indicator that lets
you know when the air filter
is dirty and needs to be
serviced.
The indicator is
located
in the air intake tube
between the air cleaner and
the engine.
See “Owner Checks and Services”
in the Index on when
to check the indicator.
If the area inside the clear section of the indicator is
green, no air filter service is required. When the area
inside the indicator is orange and
CHANGE AIR
FILTER appears, the filter should be replaced.
To remove the air filter, unhook the retaining clips and
remove the cover. Lift the filter and the connected duct
out of the air cleaner housing. Hold the duct and remove
the filter by both pulling and twisting the
filter away
fram the duct. Care should be taken
to dislodge as little
dirt as possible.
Clean the filter sealing surface of the duct and the
filter housing.
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Automatic Transmission Fluid
When to Check a1 C’ -ge
A good time to check your auromarlc transmission fluid
level
is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83 000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
0 In hilly or mountainous terrain.
0 When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions, the
fluid and filter
do not require changing.
See “Scheduled Maintenance Services’’
in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your GM dealership
Service Department. If
you do it yourself,
be sure to follow all the instructions
here, or
you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
i the fluid could come out and fall on hot engine
~ parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level
if you have been driving:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which
is 180°F to 200°F (82°C
to 93°C).
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