1994 GMC SIERRA heater

4. If the engine does not start after 15 seconds of cranking, turn the
ignition key to
OFF. Wait one minute for the starter to. cool, then try
the
same steps again.
If you’re trying
to start your engine after you’ve run out of fuel, follow the
steps in “Running Out of Fuel” (see “Diesel Fuel Requirements and Fuel
System” in the Index).
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.
I NOTICE:
If you’re not in an idling vehicle and the engine overheats, you
wouldn’t be there to see the coolant temperature gage. This \
could damage your vehicle. Don’t let your engine run when
you’re not
in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in cold weather.
Use
SAE 1OW-30 oil when the outside temperature drops below freezing.
When the outside temperature drops below
0°F (- 1 SOC), use your engine
coolant heater.
If you park your vehicle
in a garage, you shouldn’t need to use the coolant
heater
until the garage temperature goes below 0°F (-18OC), no matter how
cold it is outside.
To use the engine coolant heater, first turn off the engine. Then open the
hood, unwrap the electrical cord and plug it in. It uses normal house voltage
(I 10 volts), but:
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NOTICE:
After you’ve used the coolant 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 coolant heater plugged in? The answer
depends on the weather,
the kind of oil you have, and some other things.
Follow this chart.
Engine Coolant Heater Usage
Viscosity/ 32°F
to 0°F
Oil Grade
(OOC to -1SOC)
SAE
1 OW-30
SAE
I5W-40
Not
Required
Not
Required
0°F to -10°F
(-18” C to -23 O C)
Two
Hours*
Two
Hours*
Below -10°F
Below -23 ” C
Eight Hours* or Overnight
Eight Hours”: or Overnight
*The times listed are minimum times. It
will not harm either the coolant
heater or the vehicle
to leave the coolant heater plugged in longer than the
times stated.
For best results
in cold weather, use Number I-D diesel fuel or a
“winterized” Number 2-D fuel.
lf 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” in the Index).
If you’re not out of fuel, and your engine won’t start, do this:
Turn your ignition key to RUN. Make sure that the “GLOW PLUGS” light
is out. Then turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try starting your engine
again. And, see
your dealer as soon as you can for a starting system check.
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If the light comes on and then goes off and you know your batteries are
charged, but your engine still
won’t start, your vehicle needs service.
If the light does not come on when
the engine is cold, your vehicle needs
service.
If your batteries don’t have enough charge to start your engine, see
“Battery”
in the Index.
Be sure you have the right oil for your engine, and that you’ve changed the
oil at the proper times.
If you use the wrong oil, your engine may be harder
to start.
If
the engine starts, runs a short time, then stops, your vehicle needs service.
1 A CAUTION:
Do not use gasoline or starting “aids,” such as ether, in the air
intake.
They could damage your engine. There could also be a
fire, which could cause serious personal injury.
Engine Coolant Heater (Engine Block Heater)
In very cold weather, 0°F (-I 8°C) or colder, the engine coolant heater can
help. You’ll get easier starting and better fuel economy during engine
warm-up. Usually, the coolant heater should be plugged
in a minimum of
four hours prior to starting your vehicle.
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To use the coolant heater:
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 1 10-volt outlet.
NOTICE:
After you’ve used the coolant heater, be sure to store the \
cord as
it was before to keep it away from moving engine parts. If you
don’t, it could be damaged.
How long should you keep the coolant heater plugged in‘? The answer
depends
on the weather, the kind of oil you have, and some other things.
Instead
of trying to list everything here, we ask that you contact a GM
dealer in the area where you’ll be parking your vehicle. The dealer can give
you the best advice
for that particular area.
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Comfort Controls
Flow-Through Ventilation System
Your vehicle’s flow-through ventilation system supplies outside air to the
inside of your vehicle when
it is moving.
With the side
windows closed, air
will flow into the fro Int
Outside air will also enter the vehicle when the heater or the air
conditioning fan
is running, unless your optional air conditioner is in the
MAX mode. For more information see “MAX Button” in this section.
Ventilation Tips
0 Keep the hood and front air inlet free of ice, snow, or any other
obstruction (such
as leaves). The heater and defroster will work far
better, reducing the chance
of fogging the inside of your windows.
0 When you enter a vehicle in cold weather, turn the blower fan to HI for
a few moments before driving off. This helps clear the intake ducts of
snow and moisture, and reduces the chance of fogging the inside of
your windows.
0 Keep the air path under the front seats clear of objects. This helps air to
circulate throughout your vehicle.
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Heater Output
Engine Coolant Heater (Engine Block Heater)
If your vehicle has a diesel engine, it is equipped with an engine coolant
heater. An engine coolant heater
is optional on gas engine vehicles. You can
use an engine coolant heater during initial start-up
in cold weather (20” F,
-8” C, or lower) to help heat the passenger compartment faster. Because an
engine coolant heater warms the engine coolant, your vehicle’s heating
system can provide some heat
as soon as you start the engine.
The
use of an engine coolant heater also reduces the time it takes for the
engine to reach normal operating temperature, and shortens the time it takes
the heater to reach full output. For more information, See “Engine Coolant
Heater”
in the Index.
Diesel Engine
If you idle your diesel engine for a long time when it’s cold outside, your
heater may blow out cool air. This
is normal. When you increase the engine
speed, your heater should blow
out warmer air. If it doesn’t, your coolant
level may be low. See “Engine Coolant”
in the Index to find out how to
check your coolant level.
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Weating System (Without Air Conditioning)
If your vehicle does not have air conditioning, this is what your heating
system
will look like.
Function Le wer
The upper lever on the control panel can be moved to three different heating
functions.
0
0
0
Vent (Left): Air comes out at the vents on your instrument panel and at
your front side windows.
Heater (Center): Air comes out near the floor. This setting, along
with a heat setting, is best for cold weather.
Defrost (Right): This setting operates the defroster. Air comes out
near the bottom of the windshield and at your front side windows. Use
this setting, along
with a heat setting, when you get fog or ice on the
windshield.
Placing the lever between positions sends air out both vents.
Temperature Le wer
The lower lever on the control panel lets you select the temperature of the
air flowing into the passenger area
of your vehicle. Move the lever right
toward
“+” for warmer air. Move the lever left toward “-” for cooler air.
Fan Control Knob
The knob on the right side of the heating system control panel controls the
fan speed. The knob has four speed positions. To increase the air flow, turn
the knob toward
“+”. To decrease the air flow, turn it toward “-”.
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Temperature Selector Bar
The bar under your system display lets you select the temperature of the air
flowing into the passenger area
of your vehicle. Press COLD for cooler air
and press
HOT for warmer air. Release the bar when the system reaches the
temperature you want. The temperature is shown on
the display by the
arrow moving between
C and H.
Air Controls (BLEND)
The two buttons to the right of the system display control the air flow. You
can blend the air flow to suit your needs. The amount
of blending is shown
on the display by an arrow moving between the figure’s feet (floor air flow)
and head (vent air flow).
Left Button
Vent (Top): Press the top of this button and the air flow will come through
the instrument panel vents.
Heater (Bottom): Press the bottom of this button and the air flow will come
through the floor outlet.
The air flow can be blended between the two positions. To blend between
positions press the side of
the button showing the area where you would like
more air flow. The system will automatically begin to blend toward the
position chosen. To stop the system between positions, just press the
SAME
side of the button again.
Right Button
Defrost (Top): This setting operates the defroster. Air comes out near the
bottom
of the windshield and at your front side windows. Use this setting,
along
with a heat setting, when you get fog or ice on the windshield.
Heater (Bottom): Press the bottom of this button and air comes out near the
floor. This setting, along with
a heat setting, is best for passenger comfort in
cold weather.
The air flow can be blended between
the two positions. To blend between
positions, press the side
of the button showing the area where you would
like more air flow. The system
will automatically begin to blend toward the
position chosen. To stop the system between positions, just press the
SAME
side of the button again.
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