Tom

Dear    Tom,

Q I own a new Lexus IS350 that requires premium gas. It seems like most

foreign (European/Japanese) cars including this one require premium fuel.
Why is that and will it void my warranty if I use regular gas?

Ann—Port    Ritchie,    Florida

Ann,

A Premium gasoline is required in all vehicles that have a high-

performance engine. As a matter of fact, the engine in your new Lexus IS350
is a 3.5-liter V-6 is kicking out 306 horsepower. High-performance engines
require high-octane gas because they run hotter combustion chamber temps
than conventional engines. The lower the octane gas, the more volatile it is in
the combustion chamber. The higher the octane fuel, the less volatile and
more stable in the combustion chamber. When low-octane gas is used in a
high-output engine like yours, it causes pre-ignition or “engine knock.” The
gas ignites too early, which results in hammering at the tops of the pistons,
valve faces, and cylinder head faces. Over time this action damages the
engine, and it will fail prematurely. Use high-octane gas where
recommended. It will cost you less money in the long run, especially if you
open a warranty claim for a failed engine from a melted piston due to
prolonged use of low-octane fuel.

If you wanna play and drive high-performance cars, Annie, you gotta
pay. Buy the high-octane fuel.