octane BUICK REGAL 1998 Owners Manual

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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.
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e
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.
Fuel
The 8th digit of your vehicle identification number
(VIN) shows the code letter for your engine.
You will
find the VIN at the top left of your instrument panel.
(See “Vehicle Identification Number”
in the Index.)
If you have the 3800 engine (VIN Code K), use regular
unleaded gasoline rated at
87 octane or higher. 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.
If you have the 3800 Supercharged engine (VIN Code
l), use premium unleaded gasoline rated at 91 octane or
higher. With the 3800 Supercharged engine, in
an
emergency, you may be able to use a lower octane -- as
low as 87 -- if heavy knocking does not occur. If you
are using 9
1 or higher octane unleaded gasoline and you
hear heavy knocking, your engine needs service.
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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 damage
your 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 Buick 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
Buick dealer for service.
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