1995 GMC SIERRA fuel pump

Listed are four situations you may experience with your f~~el gage:
At the gas station. the fuel pump shuts off before the gage reads full.
It lakes a little more or less fuel to fill up than the fuel gage indicated.
For example, the gage may have indicated the tank was half
full, but it
actually took a little more or less than half the tank's capacity to fill the
, tank.
The gage moves a little when you turn a corner or speed up.
The gage doesn't go back to empty when you turn off the ignition.
None of these indicate
a problem with the fuel gage.
For information on how to fill your fuel tank, see "Fuel - Filling Your
Tank"
in the Index.
For your fuel tank capacity, see "Fuel -Tank Capacity" in the Index.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. Most of the time. the gage
pointer
will show your coolant temperature at 2 10°F (99"C), or less. But, if
you are pulling a heavy load or driving LIP hills, your coolant temperature
may rise and
fall near the red 260°F ( 128°C) mark. This is normal. If the
gage pointer moves to the red 260°F
(128°C) mark, your engine is too hot!
It means that your engine coolant has overheated. You should pull off the
road,
stop your vehicle. and turn off the engine as soon as possible.
Hot Coolant Can Burn You Badly!
In "Problems on the Road," this manual shows what to do. See "Engine
Overheating"
in thc 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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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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Fuses and Circuit Breakers
POSITION NAME
1. STOP/HAZ
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
IS.
16.
17.
18.
19.
20.
21. 22.
T CASE
CTSY
GAGES
RR HVAC
CRUISE
AUX PWR
CRANK
PARK LPS
AIR BAG
WIPER HTR-A/C
CIG LTR
ILLUM
DRL-FOG
TURN-B/U RADIO
BRAKE RADIO
BATT
TRANS
CIRCUITS PROTECTED
Stop/TCC Switch, Buzzer, CHMSL, Hazard
Lamps, Stop Lamps
Transfer Case
Courtesy Lamps, Cargo Lamp, Glove Box
Light, Dome/RDG Lamps, Vanity Mirrors,
Pwr Mirrors
IP Cluster, DRL Relay, HDLP Switch,
Keyless Entry, Low Coolant Module
RR HVAC Controls
Cruise Control
Aux Power Outlet
Diesel Fuel Pump, DERM, ECM
Lic Lamp, Park Lamp, Tail Lamp, Roof
Marker Lamp, Tail Gate Lamps, Front Side
Markers, Fog Lamp Relay, Door Switch
Illum, Fender Lamps
DERM
Wiper Motor, Washer Pump
A/C, A/C Blower, High Blower Relay
Power Amp, Cig Lighter, Door Lock Relay,
Pwr Lumbar Seat
4WD, Indicator, LP Cluster, HVAC
Controls,
RR HVAC Controls, IP Switches,
Radio Illumination
DRL Relay, Fog Lamp Relay
Frt Turn, RR Turn, B/U Lps
Radio (Ign)
DRAC, 4WAL PCM, ABS, Cruise
Radio (Batt)
PRNDL, Auto Transmission, Speedo,
Check Gages
Tell Tale
Not Used
Not Used
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