1995 GMC SIERRA fuel

Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster
to provide more air to cool the engine. In most every day
driving conditions the fan is spinning slower and the clutch is
not fully
engaged. This improves fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside temperatures, the fan
speed increases as the clutch more fully engages.
So you may hear an
increase
in fan noise. This is normal and should not be mistaken as the
transmission slipping or making extra shifts.
It is merely the cooling system
functioning properly. The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the
fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out
of a tire, it’s much more likely to
leak out slowly. But if you should ever have a “blowout,” here are a few tips
about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot
off the accelerator pedal and grip the
steering wheel firmly, Steer
to maintain lane position, then gently brake to a
stop well out of
the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your
foot from the accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well
off the road if
possible.
If a tire goes flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
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Service & Appearance Care
Section
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.
Service
Your GM dealer knows your vehicle best and wants you to be happy with it.
We hope you’ll go to your dealer for all your service needs.
You’ll get
genuine GM parts and GM-trained and supported service people.
We hope you‘ll want
to keep your GM vehicle all GM. Genuine GM parts
have one
of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you’ll want to get the
proper
GM Service Manual. It tells you much more about how to service
your vehicle than this manual can.
To order the proper service manual, see
“Service Publications”
in the Index.
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You should keep a record with all parts receipts and list the mileage and the
date
of any service work you perform. See “Maintenance Record” in the
Index.
A CAUTION:
You can be injured if you try to do service work on a vehicle
without knowing enough about it,
Be sure you have sufficient knowledge, experience, and 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.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel Requirements and Fuel
System”
in this Section. For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at 87 octane or higher. It should meet
specifications ASTM D48
14 in the United States and CGSB 3.5-92 in
Canada. These fuels should have the proper additives, so you should not
have to add anything
to the fuel.
In the United States and Canada, it’s easy to be sure
you get the right kind
of gasoline (unleaded). You’ll see UNLEADED right on the pump. And
only unleaded nozzles will
fit into your vehicle’s filler neck.
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.
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What about gasoline with blending materials that contain oxygen
(oxygenates), such
as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.” Fuel that is no more than 15%
MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel that is no more than
10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
NOTICE:
Fuel that is more than 5% methanol is bad for your vehicle.
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. And even at
5% or less, there
must be “cosolvents” and corrosion preventers in this fuel
to
help avoid these problems.
Gasolines for Cleaner Air
Your use of gasoline with deposit control additives will help prevent
deposits from forming
in your engine and fuel system. That helps keep your
engine
in tune and your emission control system working properly. It’s good
for your vehicle, and you’ll be doing your part for cleaner air.
Many gasolines are now blended with oxygenates. General Motors
recommends that
you use gasolines with these blending materials, such as
MTBE and ethanol. By doing
so, you can help clean the air, especially in
those parts of the country that have high carbon monoxide levels.
In addition, some gasoline suppliers are now producing reformulated
gasolines. These gasolines are specially designed to reduce vehicle
emissions. General Motors recommends that
you use reformulated gasoline.
By doing
so, you can help clean the air, especially in those parts of the
country that have high ozone levels.
You should ask your service station operators if their gasolines contain
deposit control additives and oxygenates, and if they have been
reformulated
to reduce vehicle emissions.
Diesel Fuel Requirements and Fuel Sysrem
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you to buy permits or pay special taxes.
Some
of these restrictions apply only to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions in any state or province, contact your auto club, the police or
other officials.
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Fuel Requirements
NOTICE:
Diesel fuel or fuel additives not recommended in this manual
could damage your fuel system and engine. Your warranty
wouldn’t cover this damage. And:
Diesel fuel that has been mixed with engine oil could damage
your engine and emission controls. Always check with your
service station operator to make sure his diesel fuel has not \
been mixed with engine oil.
If you ever run out of diesel fuel, it can be difficult to restart
your engine. “Running Out of Fuel,” later in this section, tells
you how to get it started again.
To avoid all this, try never to
let your tank get empty.
What Fuel to Use
For best results, use Number 2-D diesel fuel year-round (above and below
freezing conditionsj as oil companies blend Number
2-D fuel to address
climate differences. Number
1-D diesel fuel may be used in very cold
temperatures (when
it stays below 0°F or -18°C); however, it will produce
a power and fuel economy loss. The use of Number I-D diesel fuel in warm
or hot climates may result in stalling, poor starting when the engine is hot
and
may damage the fuel injection system.
Diesel fuel may foam when you
fill your tank. This can cause the automatic
pump nozzle to shut off, even though your tank isn’t
full. If this happens,
just wait for the foaming to stop and then continue to
fill your tank.
A CAUTION:
Heat coming from the engine may cause the fuel to expand and \
force the fuel out of your tank.
If something ignites the fuel, a
fire could start and people could be burned. To help avoid this,
fill your fuel tank only until the automatic nozzle shuts
off.
Don’t try to “top it off.”
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect
the function of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use.”
If you’re driving
in very toold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-D, you
can
use one gallon of kerosene for every two gallons of diesel fuel. Once
you add the kerosene, run your engine for several minutes
so the fuels will
mix. Add kerosene only when the temperature falls below 0°F (-1 S”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
NOTICE:
Never use home heating oil or gasoline in your diesel engine. \
They can cause engine damage.
In cold weather, your fuel filter may become clogged (waxed). To unclog it,
warm the filter to between
32°F and 50°F (OOC to 10°C). You won’t need
to replace
it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen
if a service station doesn’t regularly inspect and clean
its fuel tanks, or
if it gets contaminated fuel from its suppliers.
If this happens, a WATER
IN FUEL light will come on. If it does, the excess
water must be drained. Your dealer can show
you how to do this.
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L
WATER
IN
FUEL
If the light comes on at any other time, use this chart. This light also should
come on briefly when
you start your engine,
as
a check. If it
doesn’t, have it fixed
so it will be there to
let you know if you
ever do get water in
your fuel.
If you drive when this warning light is on, you can damage your
fuel injection system and your engine.
If the light comes on right
after you refuel,
it means water was pumped into your fuel tank.
Turn
off your engine immediately. Then, have the water drained
at once.
“WATER IN FUEL” LIGHT CHART
Problem Recommended Action
Light comes on intermittently. Drain water from fuel filter.
Light stays on:
1. At temperatures above freezing.
2. At temperatures below freezing.
3. Immediately after refueling -
large amount of water possibly
pumped into
fuel tank. Drain fuel filter
immediately.
If no
water can be drained and light stays
on, see your dealer for assistance.
Drain fuel filter immediately.
If no
water can be drained-water may
be frozen. Open the air bleed valve
to check for fuel pressure.
If no fuel
pressure is present, replace the fuel
filter.
Fuel tank purging required. See
your dealer for assistance.
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Hesitation or “flat” performance at high speed or during \
hard acceleration
may be an indication of premature fuel filter plugging due to dirty or
contaminated fuel. The fidter element may need to be changed
if this
happens. See your dealer for assistance.
To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
2. Remove the fuel tank cap.
the parking brake.
3. Place a
fuel-resistant container under the filter drain hose.
5.
6.
7.
8.
4. With the engine
off, open the
water drain valve
2 to 3 turns.
When standing in
front of the
vehicle, the valve
is located on the
right side of the
thermostat
housing.
Start the engine and allow it to idle until clear fuel is ob\
served.
Stop the engine and close the water drain valve.
Remove the fuel-resistant container and properly dispose of the
contaminated fuel.
To find out how to properly dispose of contaminated
diesel fuel see “What to Do with Used Oil” in the “E\
ngine Oil (Diesel
Engines)” part, later in this section.
Install the fuel tank cap.
If the WATER IN FUEL light comes on again after driving a short distance
or the engine runs rough or stalls-a large amount of water has probably
been pumped into the
fuel tank. The fuel tank should be purged.
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