Follow your owner’s manual. You will see one of the following; “Premium fuel required” “Premium fuel recommended” “Premium fuel not necessary” or “Do not use fuel with an Octane rating lower than 85, 86, 87, 91” and so on whichever is applicable to your vehicle. Premium fuel is formulated to protect your car’s engine from the negative side effects of lower octane fuels. Again, follow your manufacturer’s requirements for fuel.
This subject can get very complicated so a simple explanation is warranted. Octane is an additive used in gasoline causing it to be “less” combustible. Higher Octane fuels are more difficult to ignite in-cylinder. Higher Octane fuels allow more in-cylinder pressure to be engineered in – higher cylinder pressures equate to more available power from an engine.
(If you want to learn more about Octane a quick Google search will render more than you can read)
Required vs. Recommended
Pinging or Detonation
Detonation as it applies to the internal combustion engine is the negative side effect of using fuels with too low an Octane rating. Detonation occurs when in-cylinder pressure rises so quickly and so high that the fuel/air mixture spontaneously ignites separately from the spark plug ignition event. Detonation is unintentional unlike the spark ignition event which is intentional and highly timed. When there is an unwanted source of ignition within a fuel/air charged cylinder there are now two in-progress flame fronts traveling toward each other at very high speed. The flame fronts collide causing high frequency vibrations that are sometimes audible to the driver. Keep in mind that an engine can detonate and you cannot hear it. These high frequency vibrations “rattle” the piston so hard that small particles of metal begin to fall of the piston. The net result is a heavily damaged engine that will cost many thousands of dollars to repair.
If your engine does not require premium fuel you are not likely to see a benefit from using it.
If your engine is turbo or supercharged or has a high compression ratio, you are well advised to use premium fuels.
Filling up a car is so routine (and mundane) that the importance of proper fueling is often over-looked. Care should be taken in selecting your fuel grade as well as preventing rainwater or snow from entering during fueling. Also you should be adding some form of fuel system cleaner once every 10,000 miles or so.
If you are tired of getting the runaround and being treated like you haven’t got a clue, we invite you to try Colchin Automotive instead. Give us a call at 303-431-5421 for all of your automotive needs!