Gasoline Octane; Gasoline Specifications; Fuel - Pontiac 2003 Grand Prix Owner's Manual

Gasoline Specifications
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 Identification
Number (VIN) on page 5-96.
Gasoline Octane
If your vehicle has the 31 00 V6 engine (VIN Code J) or
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 it is bad enough, it can 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 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 a 87
-
if heavy
knocking does not occur. Refill your tank with premium
fuel as soon as possible. If you are using 91 octane or
higher-octane fuel and you hear knocking, your engine
needs service.
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasoline.
Canada Only
In Canada, look for the
"Auto Makers' Choice"
label on the pump.
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