Pontiac g8 Automobile User Manual


 
Gasoline Octane
If the vehicle has a V8 engine, use
regular unleaded gasoline with a
posted octane rating of 87 or higher.
If the octane rating is less than 87,
you might notice an audible knocking
noise when you drive, commonly
referred to as spark knock. If this
occurs, use a gasoline rated at 87
octane or higher as soon as possible.
If you are using gasoline rated at 87
octane or higher and you hear heavy
knocking, the engine needs service.
If the vehicle has the 3.6L V6 engine
(VIN Code 7), use regular unleaded
gasoline with a posted octane rating
of 87 or higher. For best performance
or trailer towing, you could choose
to use middle grade 89 octane
unleaded gasoline. If the octane
rating is less than 87, you might
notice an audible knocking noise
when you drive, commonly referred
to as spark knock. If this occurs,
use a gasoline rated at 87 octane
or higher as soon as possible. If you
are using gasoline rated at
87 octane or higher and you hear
heavy knocking, the engine needs
service.
Gasoline Specifications
At a minimum, gasoline should
meet ASTM specification D 4814
in the United States or
CAN/CGSB-3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See Additives on
page 8-36 for additional information.
California Fuel
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California emissions
standards, the vehicle will operate
satisfactorily on fuels meeting federal
specifications, but emission control
system performance might be
affected. The malfunction indicator
lamp could turn on and the vehicle
might fail a smog-check test. See
Malfunction Indicator Lamp on
page 4-18. If this occurs, return to
your authorized dealer/retailer for
diagnosis. If it is determined that the
condition is caused by the type of
fuel used, repairs might not be
covered by the vehicle warranty.
Driving and Operating 8-35