octane CHEVROLET EXPRESS 1998 1.G Owners Manual

Downloaded from www.Manualslib.com manuals search engine 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
0 Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
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.
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Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment
to the outside of
your vehicle.
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.
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 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.

Downloaded from www.Manualslib.com manuals search engine If your vehicle is certified to meet California Emission
1 Standards (inhcated 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 andor 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
1 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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To provide cleaner air, all gasolines in the United States
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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