Cadillac CTS-V 2009, Owner'S Manual

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Gasoline Octane
If the vehicle has the 3.6L V6 engine (VIN Code V), 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.
If the vehicle has the 6.2L supercharged V8 engine
(VIN Code P), use premium unleaded gasoline with
a posted octane rating of 91 or higher. For best
performance, use premium unleaded gasoline with a
posted octane rating of 93. In an emergency, you can use
regular unleaded gasoline with an octane rating of 87 or
higher. If 87 octane fuel is used, do not perform any
aggressive driving maneuvers such as wide open throttle
applications. You might also hear audible spark knock
during acceleration. Refill the tank with premium fuel as
soon as possible to avoid damaging the engine. If you are
using gasoline rated at 91 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 5-7
for additional information.
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