In the wake of Sandy, Long Islanders’ gas routines have changed dramatically. A simple decision to fill up has now become an hours-long process. There’s the search for an open gas station, followed by the cost-benefit analysis of the line at the rare functioning station, then the actual wait on the line. Finally, when the euphoric moment hits and an attendant waives you to the pump, you arrive only to find that the sole fuel option is the pricier, “premium” product.
For most, the pain of paying that higher price is probably short-lived; it's overshadowed by the relief that they can drive carefree for the next week or so. But is there any long-term damage being done to a typical engine by occasionally filling it with higher-octane gas?
Simply put, the more octane in a gasoline, the greater the temperature at which it ignites. In sports cars, whose engines are designed for maximum acceleration, a low-octane gas could ignite too early and cause the engine to “knock” (the sound that occurs when there’s an earlier-than-anticipated explosion in the engine’s chamber), which can eventually cause engine damage. (For a more complete explanation of this phenomenon check out this 2007 article published in Scientific American.)
However, most cars today are designed to perform well with regular gas. Check your owner’s manual, which specifies what kind of fuel is recommended. Assuming regular gas will do the trick, there’s absolutely no added benefit to filling up with premium gas, the FTC says. By the same token, there’s also no downside to filling up with premium gas — except for the extra few dollars you’ll unnecessarily hand over in the process. But in the wake of Long Island's gas shortage, that might just be the price of doing business.
By the way, even if your car's owner’s manual does recommend premium gas, it might be worth at least trying regular gas to see for yourself whether your engine knocks with old-fashioned 87-octane gas. “The only time you might need to switch to a higher octane level is if your car engine knocks when you use the recommended fuel,” the FTC says on its site. And, according to the experts on the excellent radio program Car Talk, filling up with a lower-than-recommended octane fuel probably won’t even affect your warranty.