octane GMC SIERRA 1996 Owners Manual

Your vehicle has an air bag system. Before attempting to
do your own service work, see “Servicing Your Air
Bag-Equipped Vehicle” in the Index.
You should keep,a record with all parts receipts and list
the mileage and the date
of any service work you
perform. See “Maintenance Record” in the Index.
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about
it.
0 Be sure you have sufficient knowledge,
experience, and the proper replacement
parts and tools before you attempt any
vehicle maintenance task.
0 Be sure to use the proper nuts, bolts and
other’ fasteners. “English” and “metric”
fasteners can be easily confused. If
you use
the wrong fasteners, parts can later break
or fall off.
You could be hurt.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System” in the Diesel Engine Supplement. For vehicles with gasoline engines, please
read-this.
Use regular unleaded gasoline rated at
87 octane
or higher. At a minimum, it should meet specifications
ASTM D4814
in the United States and CGSB 3.5-M93
in Canada. Improved gasoline specifications have
been developed by the American Automobile
Manufacturers Association (AAMA) for better vehicle
performance and engine protection. Gasolines meeting
the AAMA specification could provide improved
driveability and emission control system protection
compared
to other gasolines. I
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
still 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 normal,
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.
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If your vehicle is certified to meet California Emission
Standards (indicated on the underhood tune-up 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 failure. 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.
In Canada. some gasolines contain an octane-enhancing
additive called
MMT. If you use such fuels, your
emission control system performance may deteriorate
and the tnalfunction indicator lamp
on your instrument
panel may turn on. If this happens, return to your
authorized
CM dealer for service.
To provide cleaner air, all gasolines are now required to
contain additives that will help prevent deposits from
forming
in your engine and fuel system, allowing your
emission control system
to function properly. Therefore,
you should not have to add anything to the fuel. In
addition, gasolines containing oxygenates, such as ethers
and ethanol, and reformulated gasolines may be
available
in your area to help clean the air. General
Motors recommends that
you use these gasolines if they
comply with the specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use it.
It can corrode
metal parts
in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t
be covered under your warranty.
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