octane CADILLAC SEVILLE 1998 4.G Owners Manual

Downloaded from www.Manualslib.com manuals search engine Fuel
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, 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.
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. Use premium unleaded gasoline rated at
91 octane or
higher for best performance. You may
use middle grade
or regular unleaded gasolines, but your vehicle may not
accelerate as well.
At
a minimum, the gasoline you use 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 for premium is at least 91 (at
least
89 for middle grade and 87 for regular). If the octane
is less than 87, you may get a heavy knocking noise when
you
drive. If it’s bad enough, it can darnage your engine.
If you’re using fuel rated at the recommended 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
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 Cadillac 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.
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
Cadillac dealer for service. 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.
I 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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