1993 GMC SIERRA engine overheat

Section
0
This section tells you how to use your manual and includes
safety and vehicle damage warnings and symbols.
I
This section tells you how to use your seats and safety belts
properly.
2
This section explains how to start and operate your vehicle.
3
This section tells you how to adjust the ventilation and comfort
controls and how to operate your audio system.
4
Here you’ll find helpful information and tips about the road and
how to drive under different conditions.
5
This section tells you what to do if you have a problem while
driving, such as
a flat tire or engine overheating.
Here the manual tells you how to keep your vehicle running
properly and looking good.
7
This section tells you when to perform vehicle maintenance and
what fluids and lubricants to use.
8
This section tells you how to contact your GM division for
assistance and
how to get service publications. It also gives
vou information on “Reportina Safetv Defects”.
Here’s an alphabetical listing of alr..,st every subject in this
manual. You can use
it to quickly find something you want to
m read. -
V
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When your engine is cold, let it run for a few minutes before you move your
vehicle. This lets oil pressure build up. Your engine will sound louder when
it's cold.
NOTIP
-
If you're not in an idling vehicle and the engine overheats, you wouldn't
there to see the coolant temperature gage. This could damage your
hicle. Don't let vour enaine run when you're not
in vour vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in cold weather.
Use
SAE IOW-30 oil when the outside temperature drops below freezing.
When the outside temperature drops below
0°F (-18"C), use your engine
block heater.
If you park your vehicle in a garage, you shouldn't need to use \
the block
heater until the garage temperature goes below
0°F (-18"C), no matter how
cold it is outside.
To use the engine block heater, first turn
off the engine. Then open the hood,
unwrap the electrical cord and plug it in. It uses normal house voltage
(110
volts), but:
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CAUTION
Plugging the cord into an ungrounded outlet could cause an ele\
ctrical
shock.
Also, the wrong kind of extension cord could overheat and
cause a fire. You could be seriously injured. Plug the cord into a
properly grounded three-prong
11 0-volt outlet. If the cord won’t reach,
use a heavy-duty three-prong extension cord rated for at least \
15
amps.
1 NOTICE
1 After you’ve used the block heater, be sure to store the cord in th~~~~
manner it was, to help keep it away from moving engine parts.\

If YOU
don’t, it could be torn and damaged.
~p@&%?yl~
How long should you keep tne MOCK neater plugged in? The answer depends
on the weather, the kind
of oil ,you have, and some other things. Follow this-
chart.
,.
ENGINE BLOCK HEATER USAGE”
Viscosity . 32’ $0 0°F ’ 0’ to -10°F ‘Belaw -1 0°F
Grade Oil (0” to &I S‘C) ’ ’ (-18’ to. -23°C) (B&w -23°C)
SAE Not Two Eight Hours
I OW-30 Required Hours or Overnight
SAE . Nit ’ . Two Eight Hours
15W-40 f3equired Hours or Overnight
..
* The times listed are minimum. times. It will not harm &her
the block heater
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or the vehicle to leave it plugged in longer than the times stated. 3
For best results in cold weather, use Number I-D diesel fuel or a “winterized”
Number
2-D fuel.
If Your Diesel Engine Won’t- Start
If you’ve run out of fuel, look -at “Running Out Of Fuel” (see ‘‘Diesel Fuel
Requirements and Fuel System”
m the Index).
If you’re not out of fuel, and your engine won’t start, do this:
Turn y6ur ignition key
to Run. .Make sure that the GLOW PLUGS light is out.
Then turn
the ignition key to Stkrt while you ‘push the accelerator pedal
down.
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Features & Controls
To use the block heater:
1.
Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 110-volt outlet.
Plugging the cord into an ungrounded outlet could cause an electrical
- shock. Also, the wrong extension cord could overheat and cause a
fire. You could be seriously injured. Plug the cord into a properly
grounded three-prong 110-volt outlet.
If the cord won’t reach, use a
! heavy-duty three-prong extension cord rated for at least 15 amps.
After you’ve used the block heater, be sure
to store the cord in the
manner it was, to help keep it away from moving engine parts. If
you
don’t, it could be torn and damaged.
How long should you keep the block heater plugged in? The ans\
wer depends
on the weather, the kind of oil you have, and some other thi\
ngs. Instead of
trying to list everything here, we ask that you contact a Gen\
eral Motors
dealer in the area where you’ll be parking your vehicle. Th\
e dealer can give
you the best advice for that particular area.
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Leaving Your Vehicle With the Engine Running (Automatic
Transmission Models Only)
I CAUTION
A It can be dangerous to leave your vehicle with the engine running. 1
1 Your vehicle could move suddenly if the shift lever is not fully in P
(Park) with the parking brake firmly set.
If you have a four-wheel drive with a manual transfer case sh\
ift lever
and your transfer case
is in N (Neutral), your vehicle will be free to
roll, even
if your shift lever is in P (Park). So be sure the transfer
case is in a drive gear-not in
N (Neutral).
And,
if you leave the vehicle with the engine running, it could
overheat and even catch fire. You or others could be injured. Don’t
leave your vehicle with the engine running unless you have to.\

If you have to leave your vehicle with the engine running, be su\
re your
vehicle
is in P (Park) and your parking brake is firmly set, before you leav\
e
it. If you have a four-wheel drive, be sure that the transfer case i\
s in a drive
gear-not in
N (Neutral).
After you’ve moved the shift lever into the
P (Park) position, hold the regular
brake pedal down. Then, see
if you can move the shift lever away from P
(Park) without first pulling it toward you.
If you can, it means that the shift lever wasn’t fully locked into
P (Park).
Parking Your Vehicle (Manual Transmission Models Only)
Before you get out of your vehicle, put your manual transmission in R
(Reverse) and firmly apply the parking brake.
If you have four-wheel drive, be sure your transfer case is in a\
drive gear.
Your vehicle could roll
if it isn’t.
If you are parking on a hill, or if your vehicle is equipped to tow a trailer,
see “Parking on Hills” or “Towing a Trailer” in the\
Index.
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GLOW PLUGS Light
I--
GLOW
PLUGS
K2337
Your diesel engine has a special starting system. An instrument\
panel GLOW
PLUGS light tells you when the engine is ready to be started. It is at the
upper right
of your cluster. For more details, see “Starting Your Diesel
Engine” in the Index.
Low Coolant Warning Light
LOW
K2327
If you have a diesel engine, you have a low coolant warning ligh\
t. If this light
comes on, your system is
low on coolant and the engine may overheat. See
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Features & Controls
Listed are four situations you may experience with your fuel g\
age:
At the gas station, the fuel pump shuts off before the gage reads full.
It takes 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 fu\
ll, but
it
actually took a little more or less than half the tank's capa\
city 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
760
K2334
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 Coolant Can Burn You Badly!
In "Problems on the Road", this manual shows what to do. See \
"Engine
Overheating" in the Index.
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Your Driving and the Road
If you decide you can go down a hill safely, then try to keep your vehicle
headed straight down, and use a low gear. This way, engine dr\
ag can help
your brakes and they won’t have to do
all the work. Descend slowly, keeping
your vehicle under control at all times.
CAUTION
A Heavy braking when going down a hill can cause your brakes to
overheat and fade. This could cause
loss of control and a serious ‘
accident. Apply the brakes lightly when descending a hill and use a
low gear to keep vehicle speed under
control.
Q: Are there some things I should not do when driving down a hili?
A: Yes! These are important because if you ignore them you could lose
control and have a serious accident.
When driving downhill, avoid turns that take you across the in\
cline of the
hill.
A hill that’s not too steep to drive down may be too steep to drive
across. You could
roll over if you don’t drive straight down.
Never go downhill with the transmission in N (Neutral), or with the clutch
pedal depressed in a manual shift. This is called “free-whee\
ling,” Your
brakes will have
to do all the work and could overheat and fade.
Avoid braking so hard that you lock the wheels when going downhill. If
your front wheels are locked, you can’t steer your vehicle. \
If your wheels
lock up during downhill braking, you may feel the vehicle star\
ting to slide
sideways.
To regain your direction, just ease off the brakes and steer to
keep the front of the vehicle pointing straight downhill.
Q: Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But if it happens going
downhill, here’s what to do.
Stop your vehicle by applying the regular brakes. Apply the pa\
rking
brake.
Shift to P (Park) (or to Neutral with the manual transmission) and, while
still braking, restart the engine.
Shift back to a low gear, release the parking brake, and drive straight
down.
If the engine won’t start, get out and get help.
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