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Some vehicles allow you to monitor fuel mileage with the touch of a button so you actually see how your driving habits are saving – or costing – you at the gas pump. Another way to monitor and save on fuel consumption is to know the type of gas recommended for your vehicle. The following information may help you understand your vehicle’s fuel requirements and terms associated with gasoline.

Which Fuel is Right for Your Car?

The most expensive fuel may not be the best fuel for your vehicle and may hurt the performance. Most modern economy cars are designed to operate with minimum octane requirements.Performance vehicles usually require a higher octane to operate at peak performance. You should read your owner’s manual and follow the manufacturer’s recommendations.

Octane Ratings and Engine Knock

The octane ratings are regular, mid-grade, and premium/super. Premium/super is the highest octane-rated fuel. Yellow and black tags, visible on fuel pumps, represent the numerical octane ratings. Gasoline octane ratings can be described as the fuel’s ability to resist engine knocks.

Engine knock (also known as pinging, pre-ignition, detonation and spark knock), is a result of too rapid or uneven burning of the air-fuel mixture in the engine’s combustion chamber. This results in an internal knocking noise in the engine. The higher the octane rating, the slower the fuel burns and the greater the resistance it has to engine knock. Engine knock also can be caused by several other factors. In most cases an engine knock is a result of a control problem, such as improper ignition timing, carbon deposits in the engine, a malfunctioning exhaust gas recirculation valve system, an engine that is running too hot, or simply an engine that has worn with age.

If your vehicle is knocking, and all mechanical areas check out okay, it may be time to switch to another brand of fuel. Octane ratings can vary from brand to brand, and switching brands may be the answer to correcting engine knock.

If the vehicle manufacturer recommends regular gasoline, higher octane-rated fuel will not provide more engine power, burn cleaner or improve fuel economy in vehicles that are in good mechanical condition.

Manufacturer Recommendations

If the manufacturer recommends using mid-grade or premium fuel, it is important to follow that recommendation. Most modern vehicles are equipped with a sensor that detects engine knock. If a lower-rated fuel is used and engine knock is detected, the sensor will send a signal to the vehicle’s computer. The computer will react to that signal and adversely effected engine performance occurs.

Quick Tip

If you see a fuel tanker refilling a gas pump, try a different gas station for your fill-up. Freshly filled fuel pumps are not your best option. When the gasoline from the tanker is poured into the in-ground tanks, it stirs up water and debris that has settled at the bottom of the in-ground tank. If you fill your tank, it will most likely contain the water and debris.