1994 GMC SIERRA light

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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1
I 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.
5. Start the engine and allow it to idle until clear fuel is observed.
6. Stop the engine and close the water drain valve.
7. 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 “Engine Oil (Diesel
Engines)” part, later
in this section.
8. 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.
A CAUTION:
Diesel fuel containing water is still flammable. You could be
burned. If
you ever try to drain water from your fuel, keep
sparks, flames
and smoking materials away from the mixture.
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You should also use the proper viscosity oil for your vehicle, as shown in
the following chart:
LIGHT DUTY EMISSIONS -GAS ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE VISCOSITY GRADE OIL
FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
F
tlOO -
+80 -
+60 -
+40 -
+20 -
0-
C
t 38
t 27
t 16
t4
-7
- 18
m LOOK
ONE OF THESE
LABELS
-- -1 -I SAE 1OW-30
IF NEITHER SAE 5W-30 NOR SAE 1OW-30
5w-30 GRADE OILS ARE AVAILABLE, SAE 30
PREFERRED GRADE MAY BE USED AT TEMPERATURES
ABOVE
40 DEGREES F (4 DEGREES C).
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR
ANY OTHER GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE SW-30 is best for your vehicle. However, you
can use SAE 1OW-30 if it’s going to be 0°F (-1 8°C) or above. These
numbers on an
oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE lOW-40 or SAE 20W-50.
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If you cannot find oils with the new “starburst” symbol on the front of the
container,
you should look for and use oils containing the following three
things:
SHor SG
“SH” or “SG” must be on the oil container, either by itself or combined
with other quality designations, such as “SH/CD,” “SH,SG,CD,”
“SG/CD,” etc. These letters show American Petroleum Institute (API)
levels of quality.
0 SAE 5W-30 -Vehicles with Light Duty Emissions (SSOO GVWR or
less) OR
SAE 1 OW-30 -Vehicles with Heavy Duty Emissions (850 1 GVWR or
more).
0 Energy Conserving I1
Oils with these words on the container will help you save fuel.
These three things are usually included
in a doughnut shaped logo (symbol)
on most containers. If you cannot find oils with the “starburst” symbol, you
should look for oils with the doughnut shaped symbol, containing the three
things noted above.
NOTICE:
If you use oils that do not have either the “starburst” symbol or
an
API SH or SG designation, you can cause engine damage not
covered by your warranty.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
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Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
It’s below freezing outside and most trips are less than 10 miles
(16 km).
The engine is at low speed most of the time (as in door-to-door
delivery, or
in stop-and-go traffic).
You tow a trailer often.
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one
of these is true for your vehicle, then you need to change your oil
and-filter every 3,000 miles (5 000 km) or 3 months - whichever comes
first.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months
- whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles (10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change
your oil. If time determines when you change your oil, change the
filter each time you change your oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (- 18°C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
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Then, follow these steps:
I. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of the filler plug hole.
3. If the fluid level is good, install the plug and be sure it is fully seated. If
the fluid level is low, add more fluid as described in the next steps.
How to Add fluid
Here’s how to add fluid. Refer to the Maintenance Schedule to determine
what kind
of fluid to use. See “Recommended Fluids and Lubricants” in the
Index.
I. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough fluid to bring the
fluid level up to
the bottom of the filler plug hole.
3. Install the filler plug. Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch in your vehicle is self-adjusting. A slight amount of
play (1/4 inch to 1/2 inch) in the pedal is normal.
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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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To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark,
or a little higher. When your engine is warm, the level should be above the
COLD mark.
If this light comes on,
it means you’re low
on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix at the surge tnnk, but only
when the engine is cool.
Open the air bleed valve on the thermostat housing to allow trapped air
out
of the system. Close the bleed valve when coolant begins to flow out.
I A CAUTION:
nrning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow
out:
and burn you badly. Never turn the surge tank pressure cap -
even a little - when the engine and radiator are hot.
A CAUTION:
You can be burned if you spill coolant on hot engine parts.
Coolant contains ethylene glycol, and it will burn if the engine
parts are hot enough. Don’t spill coolant on
a hot engine.
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