Fuel; Recommended Fuel - Cadillac 2014 ATS Owner's Manual

9-62 Driving and Operating

Fuel

Use of the recommended fuel is an
important part of the proper
maintenance of this vehicle. When
driving in the U.S., to help keep the
engine clean and maintain optimum
vehicle performance, we
recommend using TOP TIER
Detergent Gasolines. See
www.toptiergas.com for a list of TOP
TIER Detergent Gasolines.
If the vehicle has a yellow fuel cap,
E85 or FlexFuel can be used in the
vehicle. See
.

Recommended Fuel

If the vehicle has a 2.5L L4 engine
or a 3.6L V6 engine, use regular
unleaded gasoline with a posted
octane rating of 87 or higher. If the
octane rating is less than 87, an
audible knocking noise, commonly
referred to as spark knock, might be
heard when driving. If this occurs,
use a gasoline rated at 87 octane or
higher as soon as possible. If heavy
knocking is heard when using
gasoline rated at 87 octane or
higher, the engine needs service.
If the vehicle has the 2.0L L4
engine, use premium unleaded
gasoline with a posted octane rating
of 91 or higher. You can also use
regular unleaded gasoline rated at
87 octane or higher, but the
vehicle's acceleration could be
slightly reduced, and a slight audible
knocking noise, commonly referred
to as spark knock, might be heard.
If the octane is less than 87, a
heavy knocking noise might be
heard when driving. If this occurs,
use a gasoline rated at 87 octane or
higher as soon as possible.
Otherwise, you could damage the
engine. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.
Use of Seasonal Fuels
Use summer and winter fuels in the
appropriate season. Driving or
starting could be affected if the
incorrect fuel is used. Drive the
vehicle with the engine running until
the fuel is a half tank or less, then
refuel with the current seasonal fuel.
Prohibited Fuels
Gasolines containing oxygenates,
such as ethers and ethanol, as well
as reformulated gasolines are
available in some cities. If these
gasolines comply with the
previously described specification,