What is a possible consequence of using fuel with an octane rating higher than specified for a particular engine?

Using fuel with an octane rating higher than specified for a particular engine can lead to fouling of spark plugs, which can negatively affect engine performance. When an engine is designed for a specific octane rating, it means that it utilizes the properties of the fuel in a way that optimizes combustion efficiency. High-octane fuels are formulated to withstand higher pressures and temperatures without igniting prematurely. If an engine does not require this higher resistance to detonation and instead uses fuel that is intended for higher performance applications, it may lead to incomplete combustion or other combustion byproducts that result in the fouling of spark plugs.

Fouled plugs can interrupt the spark and negatively impact the fuel-air mixture’s ignition process, causing issues such as rough idling, poor acceleration, or difficulty starting the engine. This happens because the residues from the unburned fuel can accumulate on the spark plugs, making them less effective in igniting the fuel mixture.

In contrast, while improved engine efficiency, increased fuel consumption, and better acceleration could sound appealing, they do not accurately apply to the scenario of mismatched octane ratings. Engines are designed to operate optimally with fuels of a specified octane rating, and using fuel with a higher octane than