1998 GMC SIERRA gas type

Be sure the posted octane is at least 87. If the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don’t worry if you hear a little pinging noise when
you’re accelerating or driving
up a hill. That’s norlnal,
and you don’t have to
buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications.
If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission control system
performance may be affected. The malfunction indicator lamp
on your instrument
panel may turn on and/or your
vehicle may fail
a smog-check test. If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause
of’ fdilure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does not recommend the
use
of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator
lamp on your instrument panel
may
turn on. If this occurs, return to your authorized
GM dealer for service.
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~ Be
careful not to spill gasoline. Clean gasoline from
~ painted surfaces as soon as possible. See “Cleaning the
i Outside of Your Vehicle” in the Index.
When you put
the cap back on, turn it to the right
(clockwise)
until you hear a clicking sound. Make sure you
fully install the cap. The diagnostic system can determine if
the fuel cap has been left off or improperly installed. This
would allow fuel to evaporate into the atmosphere. See
“Malfunction Indicator Lamp”
in the Index.
NOTICE:
If you need a new cap, be sure to get the right
type. Your dealer can get one for you. If you get
the wrong type, it may not
fit properly. This may
cause your malfunction indicator lamp to light
and your fuel tank and emissions system may be
damaged. See ‘LMalfunction Indicator Lamp” in
the Index.
Filling a Portable Fuel Container
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from the
container can ignite the gasoline vapor. You can
be badly burned and your vehicle damaged
if this
occurs.
To help avoid injury to you and others:
Dispense gasoline only into
approved containers.
Do not fill a container while it is inside a
vehicle, in
a vehicle’s trunk, pickup bed or
on any surface other than the ground.
inside of the
fill opening before operating
the nozzle. Contact should be maintained
until the filling is complete.
0 Bring the fill nozzle in contact with the
0 Don’t smoke while pumping gasoline.
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Radiator Pressure Cap
(Gasoline Engine)
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.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
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Battery
Every new vehicle has an ACDelco Freedom@ battery.
You never have to add water to one of these. When it’s
time for a new battery, we recommend an ACDelco
Freedom battery. Get one that has the replacement
number shown
on the original battery’s label.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days
or more, remove the black, negative
(-) cable from
the battery. This
will help keep your battery from
running down.
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if
you
aren’t careful. See “Jump Starting” in the Index
for tips on working around
a battery without
getting hurt. Contact
your dealer to learn how
to prepare your vehicle
for longer storage periods.
Also, for your audio system. see “Theft-Deterrent
Feature”
in the Index.
Bulb Replacement
Before you replace any bulbs, be sure that all the lamps
are off and the engine isn‘t running. See “Replacement
Bulbs”
in the Index for the proper types of bulbs to use.
1 6!!, CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb.
You or
others could be injured. Be sure to read
and
follow the instructions on the bulb package.
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