1994 GMC SIERRA Owners Manual

Cold Weather Operation
In cold weather (below 20”F, or -7”C), use 1-D or “Winterized” Number
2-D fuel (a blend of I-D and 2-D). Be sure you get the right fuel. In very
cold temperatures (when
it stays below 0°F or -1 8OC), use Number 1-D.
If you’re driving in very cold temperatures and can’t get Number I-D or a
“winterized” Number
2-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 8” 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), especially if
you use Number
2-D diesel fuel that hasn’t been “winterized.” To unclog it,
warm the filter to between 32°F and 50°F (0°C 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 do this
for you.
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.
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If the light comes on at any other time, use this chart.
“Water in Fuel” Light Chart
Problem
Light comes on intermittently.
Light stays on:
1. At temperatures above
freezing.
2. At temperatures below
freezing.
Recommended Action
Drain water from fuel filter.
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.
3. Immediately after refueling - Fuel tank purging required. See
large amount of water possibly your dealer for assistance.
pumped into fuel tank.
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 filter element may need to be changed
if this
happens. See your dealer for assistance.
NOTICE:
If you drive when this warning light is on, you can damage y\
our
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.
To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
the parking brake.
2. Remove the fuel tank cap.
3. Place a fuel-resistant container under the filter drain hose.
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1
I 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.
5. Start the engine and allow it to idle until clear fuel is observed.
6. Stop the engine and close the water drain valve.
7. 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 “Engine Oil (Diesel
Engines)” part, later
in this section.
8. 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.
A CAUTION:
Diesel fuel containing water is still flammable. You could be
burned. If
you ever try to drain water from your fuel, keep
sparks, flames
and smoking materials away from the mixture.
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~ NOTICE:
If
there is water in your diesel fuel and the weather is warm or
humid, fungus and bacteria can grow in the fuel. They can
damage your fuel system. You'll need
a diesel fuel biocide to
sterilize your fuel system. Your dealer can advise you if you ever
need this.
If your fuel tank needs to be purged to remove water, see your
dealer or
a qualified technician. Improper purging can damage
your fuel system.
Running Out of Fuel (Diesel Engines)
If the engine stalls and you think that you've run out of fuel, do this:
First, open the fuel
filter
air bleed valve.
If there is air, then you are probably out of
fuel.
To restart your engine:
1. If you're parked on a level surface, add at least two gallons of fuel.
However, if you're parked on a slope, you may need to add up to five
gallons of fuel.
2. With the air bleed valve open, turn your ignition key to "Sta\
rt" for 10
to 15 seconds to crank (but not start) your engine. Wait one minut\
e
between intervals of cranking to allow the starter motor to cool.
Overheating the starter could damage it. Keep doing this until you can
just see some clear fuel at the air bleed valve. (If, during this ste\
p, the
engine starts, turn the ignition
off and close the valve before restart.)
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A CAUTION:
Diesel fuel is flammable. It could start a fire if it gets on hot
engine parts. You could be burned. Don’t let too much fuel flow
from the air bleed valve, and wipe up any spilled fuel with
a
cloth.
3. Close the air bleed valve.
4. Turn the ignition key to “Start” for 10 to 15 seconds at a time until your
engine starts.
Fuel Filter Replacement (Diesel Engines)
If you want to change the fuel filter yourself, here’s how to do it:
Before you remove the filter, drain any water that may have collected in the
fuel filter or filter head. See “Water in Fuel” earlier in this section to find
out how to remove water from the fuel system.
Then, drain
fuel from the filter by opening the air bleed valve and the water
drain valve. This prevents the fuel from spilling as
you replace the filter.
Drain the fuel into
a fuel-resistant container and dispose of it properly.
A CAUTION:
Diesel fuel is flammable. It could start a fire if something ignites
it, and you could be burned. Don’t let it get on hot engine parts,
and keep matches or other ignition sources away.
I. Turn off the engine and apply the parking brake.
2. Take off the fuel tank cap. This releases vacuum in the tank.
3. The filter is located at the rear of the intake manifold.
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4. Unscrew and
remove the ring
nut from the top
of the filter head.
7. Line up the
writing on the top
of the filter
so it
faces (is readable
from) the front of
the vehicle. Push
the element in
until the mating
surfaces touch.
5. Lift the element
out of the filter
head.
6. If there is any dirt
on the element
sealing surface of
the filter head,
clean it
off.
8. With the air bleed valve open, turn your ignition key to START for 10
to 15 seconds. Wait one minute for your starter to cool. Do this until
you can see clear fuel coming from the air bleed valve.
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9. Close the air bleed valve and replace the fuel cap.
10. Start your engine and let it idle for five minutes. Check your fuel filter
and air bleed valve for leaks.
Fuels in Foreign Countries
If you plan on driving in another country outside the U.S. or Canada,
unleaded fuel may be hard to find. Do not use leaded gasoline.
If you use
even one tankful, your emission controls won’t work well or at all. With
continuous use, spark plugs can get fouled, the exhaust system can corrode,
and your engine oil can deteriorate quickly. Your vehicle’s oxygen sensor
will be damaged. All of that means costly repairs that 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
L1H 8P7
Filling Your Tank
The fuel cap is behind
a hinged door on the
left side of your
vehicle.
/i CAUTION:
Gasoline vapor is highly flammable. It burns vioIently, and tha\
t
can cause very
bad injuries. Don’t smoke if you’re near gasoline
or refueling your vehicle. Keep sparks, flames, and smoking
materials away from gasoline.
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While refueling, hang the cap inside the fuel
door.
To take off the cap,
turn it slowly to the
left.
Be careful not to spill gasoline. Clean gasoline from painted \
surfaces 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 a clicking
noise.
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 €it or
have proper venting, and your fuel tank and emissions system
might be damaged.
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