1994 GMC SIERRA fuel pump

Gages
Fuel Gage
Standard Cluster -Gas Standard Cluster --Diesel
Tachometer Cluster -Gas Tachometer Cluster --Diesel
The fuel gage, when the ignition is on. tclls you about how much fuel you
have left
in your tank. The gage will first indicate empty before you are out
of fuel, and you should get Inore fuel as soon 11s possiblc.
Listed are four situations you may experience
with your fuel gage:
At the gas station. the fuel pump shuts off before the gage reads full.
0 It takes a little more or less fuel to fill up than thc I’wI gage indicated.
For example, the gage may have indicatcd thc tank was half full. but it
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NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
__ .
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains the
maintenance your new vehicle needs, and when
it should be done. It also
has a form that you can use to record the maintenance work done on your
vehicle. Be sure
to read this information.
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 U.S. 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 U.S. 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.
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.
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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 conditions) as oil companies blend number
2-D fuel to address
climate differences. Number
1-D diesel fuel may be used in below freezing
weather, however, it will produce a power and
fuel economy loss. The use
of number
1-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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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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