1994 GMC SIERRA overheating

Table of Contents
Introduction - How to Use this Manual
This section tells you how to use your manual and includes safety
and vehicle damage warnings and symbols.
Section 1 - Seats and Safety Restraints
This section tells you how to use your seats and safety restraints
properly.
Section 2 - Features & Controls
This section explains how to start and operate your Vehicle.
Section 3 - Comfort Controls & Audio Systems
This section tells you how to adjust the ventilation and comfort
controls and how to operate your audio system.
Section 4 - Your Driving and the Road
Here you’ll find helpful information and tips about the road\
and
how to drive under different conditions.
Section 5 - Problems on the Road
This section tells you what to do if you have a problem while
driving, such as
a flat tire or engine overheating.
Section 6 - Service & Appearance Care
Here the manual tells you how to keep your Vehicle running
properly and looking good.
Section 7- Schedule Maintenance Services
This section tells you when to perform vehicle maintenance and
what fluids and lubricants to use.
Section 8 - Customer Assistance Information
This section tells you how to contact your GM division for
assistance and
how to get service publications. It also gives you
information on “Reporting Safety Defects” on page
8-4.
Index
Here’s an alphabetical listing of almost every subject in th\
is
manual. You can use
it to quickly find something you want to read.
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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. If the gage pointer moves
into the red area, about
260” F ( 145” C) or more, your engine is too hot! It
means that your engine coolant has overheated. If you have been operating
your vehicle under normal operating conditions, you should pull off the
road, stop
your vehicle, and turn off the engine as soon as possible.
Hot Cooianf Can Burn You Badly!
In “Problems on the Road,” this ~nanual shows what to do. See “Engine
Overheating”
in the Index.
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Driving On Grades
Reduce speed and shift to a lower gear before you start down a long or
steep downgrade.
If you don’t shift down, you might have to use your
brakes
so much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to around
45 mph
(70 km/h) to reduce the possibility of engine and transmission overheating.
When towing at high altitude with steep uphill grades,you need to consider
the following information. The lower atmospheric pressure at high altitude
allows your vehicles engine coolant to boil at a lower temperature than at
normal altitudes.
If you immediately turn your engine off after towing at high altitude with
steep uphill grades, your vehicle may show signs similar
to engine
overheating.
To avoid this, let your vehicle operate in a parked position with
the transmission in
“N” (Neutral) for a few minutes before you turn off the
engine. If you do get the overheat warning, see “Engine Overheating” in
the Index.
If you have an automatic transmission, you should use
“D” (or, as you need
to, a lower gear) when towing a trailer. Operating your vehicle in
“D” when
towing a trailer will minimize heat buildup and extend the life
of your
transmission.
If you have a manual transmission and
you are towing a trailer, it’s better
not to use fifth gear. Just drive in fourth gear (or, as you need to, a lower
gear).
Parking on Hills
You really should not park your vehicle, with a trailer attached, on a hill. If
something goes wrong, your rig could start
to move. People can be injured,
and both your vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill, here’s how
to do it:
1.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into “P’ (Park) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are in place, release the regular brakes until the
chocks absorb
the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift to
“P7, (Park), or “R” (Reverse) for a manual transmission.
If
you have a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in
“N7 (Neutral).
Release
the regular brakes.
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Problems on the Road
Section
Here you’ll find what to do about some problems that can occur on the road .
Hazard Warning Flasher ..................................... 5-2
Other Warning Devices ...................................... 5-3
Jumpstarting .............................................. 5-3
TowingYourVehicle ........................................ 5-7
Engine Overheating ........................................ 5-11
Engine Fan Noise .......................................... 5-25
If a Tire Goes Flat ......................................... 5-25
Changing
a Flat Tire ..................................... 5-26
Jackstorage
........................................... 5-29
SpareTire
............................................. 5-29
If You’re Stuck:
In Sand. Mud. Ice or Snow ..................... 5-40
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,ngine Overheating
You will find a coolant temperature gage on your vehicle instrument panel.
If you have a diesel engine, you will also find a low coolant light on your
instrument panel.
If Steam 1s Coming From Your Engine
NOTICE:
If your engine catches fire because you keep driving with no
coolant, your vehicle can be badly damaged. The costly repairs
would not be covered by your warranty.
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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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What to use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants”
in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle
will:
Give freezing protection down to -20 OF (-29”C), or -34°F (-37°C) in
Canada and for vehicles with the cold climate option.
Give boiling protection up to 258 OF ( 125 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half clean wuter (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M” with a complete coolant flush and refill. If you use
this mixture, you don’t need to add anything else.
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Radiator Pressure Cap-Gas Engines
The radiator pressure
cap must be tightly
installed with the
arrows
on the cap
lined
up with the
overflow tube
on the
radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa) pressure-type cap and
must be tightly installed to prevent coolant
loss and possible
engine damage from overheating. Be sure the arrows
on the cap
line
up with the overflow tube on the radiator filler neck.
Surge Tank Pressure Cap- Diesel Engines
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