Fuel; Gasoline Octane - Pontiac 2003 Bonneville Owner's Manual

Fuel
The 8th digit of your vehicle identification number (VIN)
shows the code letter or number that identifies your
engine. You will find the VIN at the top left of the
instrument panel. See Vehicle ldentification Number
(VIN) on page 5-90.
Gasoline Octane
If your vehicle has the 3800 V6 engine (VIN Code K),
use regular unleaded gasoline with a posted octane
of 87 or higher. If the octane is less than 87, you
may get a heavy knocking noise when you drive.
If this occurs, use a gasoline rated at 87 octane or
higer as soon as possible. Otherwise, you might
damage your engine. A little pinging noise when you
accelerate or drive uphill is considered normal.
This does not indicate a problem exists or that a
higher-octane fuel is necessary. If you are using
87 octane or higher-octane fuel and you hear heavy
knocking, your engine needs service.
If your vehicle has the 3800 Supercharged V6 engine
(VIN Code I ) , use only premium unleaded gasoline with
a posted octane of 91
or
higher. In an emergency,
you may be able to use a lower octane
-
as low
as 87
-
if heavy knocking does not occur. Refill
your tank with premium fuel as soon as possible.
Otherwise, you might damage your engine. If you are
using 91 octane or higher-octane fuel and you hear
heavy knocking, your engine needs service.
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