1993 GMC SIERRA fuel cap

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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Service & Appearance Care
This light also should come on 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.
If the light comes on at any other time, use this chart.
“WATER IN FUE
PROBLEM
Light comes on intermittently.
1) Temperatures above freezing.
Light stays on
2) Temperatures below freezing.
3) Immediately after refueling -
Large amounts of water
probably pumped into the
tank.
.” LIGHT CHART
RECOMMENDED ACTION
Drain water from fuel filter.
Drain fuel filter immediately.
If nc
water is drained and light stays on
-
replace fuel filter.
Drain fuel filter immediately.
If no
water can be drained
- water may be
frozen. Open air bleed
to check for
fuel pressure.
If no fuel pressure
replace filter.
Fuel tank purging required. See your
dealer for assistance.
1
iesitation or “flat” performance at high speed or hard acceleration may be an
ndication 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
or assistance.
f you drive when this warning light is on, you can damage your fuel I
njection system and your engine. If the light comes on right after you
efuel,
it means water was pumped into your fuel tank. Turn off your
mgine immediately. Then, have the water drained at once.
I
To drain water:
1. Remove the fuel tank cap.
2. Connect a hose going from the water drain valve to a fuel-resistant
container.
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7
F
K2451
..
3. With the engine off, open the water drain valve 2 to 3 turns.
4. Start the engine and allow it to idle for 1 to 2 minutes, or until clear fuel
is observed.
5. Stop the engine and close the water drain valve.
6. 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.
~ CAUTION I
A Diesel fuel containing water is still flammable. You could h~ burmi.
If you eve:r try to drain water from your fuel, kee,p sparks mes d.
. smoking materials away from the mixture.
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 service technician. Improper purging can damage your fuel
system.
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2. Unplug the Shut-Off solenoid wire from the fuel pump to prevent the
engine from starting.
3. With the air bleed valve open, turn your ignition key to Start for 10 to
15 seconds to crank (but not start) your engine. Keep doing this until
you can just see some clear fuel at the air bleed valve.
I A Diesel fuel is flammable. It could start a fire if it gets on hot engine
b parts. You could be burned. Don’t let too much fuel flow from the air
bleed valve or screw, and wipe up any spilled fuel with a cloth.
4. Close the air bleed valve, or replace the screw and reconnect \
the
Shut-Off solenoid wire.
5. Turn the ignition key to Start for 10 to 15 seconds at a time until your
engine starts.
Fuel Filter Replacement (6.5L Diesel Engines)
If you want to change the fuel filter yourself, here’s how \
to do it:
1 CAUTION
A Diesel fuel is flammable. It could start a fire if something ignites it,
-L and you could be burned. Don’t let it get on hot .engine parts, and
I keep matches or other ignition sources away.
1. Turn off your engine and set your parking brake.
2. Take off the fuel tank cap. This releases pressure in the tank.
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6. Open the air bleed valve.
7. Turn your ignition key to Run for 10 to 15 seconds. Wait one minute for
the starter to cool. Do this until you can see clear fuel coming from the
air bleed valve.
8. Close the air bleed valve and replace the fuel tank cap.
9. Start your engine and let it idle for five minutes. Be sure to check your
fuel filter for leaks.
Fuel Filter Replacement (62 Diesel Engines)
If you want to change the fuel filter yourself, here's how to do it:
'1
K2667
Drain fuel from the filter by opening the air bleed valve and\
the water drain
valve. This prevents the fuel from spilling as you replace the\
filter. Drain the
fuel into a fuel-resistant container and dispose of it properly.
CAUTION I
A
Diesel fuel is flammable. It could start a fire if something ignites it,
and you could be burned. Don't let it get on
hot engine parts, and
keep matches
or other ignition sources away.
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Service & Appearance Care
To remove the filter:
1. Turn off your engine and set your parking brake.
2. Take off the fuel tank cap. This releases pressure in the tank.
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K2669
3. The filter is behind the air cleaner on the intake manifold. Using a
4. If there is any dirt on the fuel port seal of the filter adapter, clean \
it off.
5. Snap the new filter into position with the bail wires.
screwdriver, separate both bail wires. Take out the filter.
K2671
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6. Close the water drain valve and connect a hose going from the air bleed\

valve port
to a fuel-resistant container. The inside diameter of the hose
should be one-eighth of an inch.
for the starter to cool.
Do this until you can see clear fuel coming from
the air bleed valve.
7. Turn your ignition key to Start for 10 to 15 seconds. Wait one minute
8. Close the air bleed valve and replace the fuel tank cap.
9. Start your engine and let it idle for five minutes. Be sure to check your
fuel filter for leaks.
Fuels in Foreign Countries (Gasoline Engines)
If you plan on driving in another country outside the US. or Canada,
unleaded fuel may be hard to find.
Do not use leaded gasoline. If you use
even one tank full, 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 three-way catalytic
converter and 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 of Canada Ltd.
International Export Sales
Post Office Box
828
Oshawa, Ontario L1H 7N1, Canada
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I CAUTION
* If you get gasoline on you and then something ignites it, you co\
uld
1 be badly burned. Gasoline can spray out on you if you open the fuel
filler cap too quickly. This spray can happen
if your tank is nearly
full, and is more likely in hot weather. Open the fuel filler\
cap slowly and wait for any "hiss" noise
to stop.
I Then unscrew the cap all the way. I
When you put the cap back on, turn it tc "le :clo-'hise) until you hear
a clicking noise.
I NOTICE
~f you need a new cap, be sure to get the right type. Your dealer can get 1
me for you. If you get the wrong type, it may not fit or -have proper
denting, and your fuel tank and emissions system might be damaged.
Checking Things Under the Hood
U
K2609
Hood 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. Lift t\
he hood.
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