octane CHEVROLET EXPRESS 1996 1.G Owners Manual

Downloaded from www.Manualslib.com manuals search engine Your vehicle may have an air bag system. If it does, see
“Servicing Your Air Bag-Equipped Vehicle”
in the
Index before attempting to do your own service work.
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.
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 D48 14 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.
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
ofpinging.
It’s the heavy, constant knock that means
you have a problem.
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Downloaded from www.Manualslib.com manuals search engine 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 hilure. 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 malfunction indicator lamp
on your instrument
panel
may turn on. If this happens, return to your
authorized GM 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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