Turbo models
Except STI
The engine is designed to operate using premium unleaded gasoline with an octane rating of 91 AKI (95 RON) or higher. If premium unleaded gasoline is not available, regular unleaded gasoline with an octane rating of 87 AKI (90 RON) or higher may be temporarily used. For optimum engine performance and driveability, it is required that you use premium grade unleaded gasoline.
NOTE
Be sure to use premium unleaded gasoline of 91 AKI (95 RON) or higher.
If other gasoline (lower than 91 AKI (95 RON)) is used, knocking, reduced output and poor accelerator response will result.
STI
The engine is designed to operate at maximum performance using unleaded gasoline with an octane rating of 93 AKI (98 RON) or higher. If 93 AKI (98 RON) fuel is not readily available in your area, unleaded gasoline with an octane rating of 91 AKI (95 RON) may be used with no detriment to engine durability or driveability.
However, you may notice a slight decrease in maximum engine performance while using 91 AKI (95 RON) fuel.
Use of 91 AKI (95 RON) fuel will not affect your warranty coverage.
See also:
New Chassis Tuning for 2011
The Subaru Impreza WRX STI was already a highly optimized performance
machine. Specific chassis tuning. Aluminum front lower L-arms reduce unsprung
vehicle weight. Major chassis tuning changes inc ...
Turn signal indicator lights
These lights show the operation of the turn signal or lane change signal.
If the indicator lights do not blink or blink rapidly, the turn signal bulb may be burned out. Replace the bulb as soon as ...
Cooling system
Never attempt to remove the radiator cap until the engine has been shut off and has cooled down completely. Since the coolant is under pressure, you may suffer serious burns from a spray of boilin ...