1994 GMC SIERRA check engine

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 section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
...................................... 6-4
Diesel Fuel Requirements and Fuel System
...................... 6-5
Checking Things Under the Hood
............................. 6-15
HoodRelease
.......................................... 6-15
Cleaning Your Diesel Engine
.............................. 6-16
Noise Control System .................................... 6-16
Engine Oil (Except Diesel)
................................ 6-17
Engine Oil (Diesel Engines)
............................... 6-24
iri
Air Cleaner ............................................ 6-29
Automatic Fluid ........................................ 6-30
ManualFluid
........................................... 6-33
Hydraulic Clutch
........................................ 6-34
RearAxle ............................................. 6-35
mnsfer Case
.......................................... 6-36
FrontAxle
............................................. 6-37
Engine Coolant
......................................... 6-38
Power Steering Fluid
.................................... 6-43
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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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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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Checking Things Under the Hood
Iood Release
To open the hood, first
pull the handle inside
the vehicle.
Then go to the front
of
the vehicle and pull up
on the secondary hood
release, located just to
the passenger side of
the center of the grill.
Lift the hood.
Your vehicle,
if it has
air conditioning, may
have a auxiliary engine fan in addition
to the belt driven fan.
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Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing thereof:
1 . The removal or rendering inoperative by any person, other than for
purposes
of maintenance, repair or replacement, of any device or
element
of design incorporated into any new vehicle for the purpose of
noise control, prior to its sale or delivery to the ultimate purchaser or
while
it is in use; or
2. The use of the vehicle after such device or element of design has been
removed or rendered inoperative by any person.
Among those acts presumed to constitute tampering are the acts listed
below.
Insulation:
Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor (if so equipped)
inoperative
so as to allow engine speed to exceed manufacturer
specifications.
Fan and Drive:
Removal of fan clutch (if so equipped) or rendering clutch inoperative.
Removal of fan shroud (if so equipped).
Air Intake:
Removal of air cleaner silencer.
Reversing air cleaner cover.
Exhaust:
Removal of muffler and/or resonator.
Removal of exhaust pipes and exhaust pipe clamps.
Engine Oil (Except Diesel)
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.
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To Check Engine Oil
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.
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 lower.
When to Add Oil
If the oil is at or below the ADD mark, then you’ll need to add some oil. But
you must use the right kind. This section explains what kind of oil
to use.
For crankcase capacity, see “Capacities and Specifications”
in the Index.
NOTICE:
Don’t add too much oil. If your engine has so much oil that the
oil level gets above the upper mark that shows the proper
operating range, your engine could be damaged.
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