High-octane fallacy: Experts warn premium fuel not always the best bet

Experts in the automotive industry note that the so-called premium fuels, often touted as more efficient or sporty, might not always be the best vehicle choice. For older cars, these fuels could even be detrimental.

Gas stations market these pricier options as entirely safe and exceptionally beneficial, yet mechanics are split. Research by the ADAC organization indicates that using the highest-quality fuels can reduce consumption by approximately 1-5 per cent.

Adam Lehnort, an expert from the ProfiAuto Serwis network, explains, based on mechanics' experiences, that specially refined fuels could potentially cause damage. The cleaning additives they contain can dislodge deposits of accumulated impurities, which then migrate into the engine oil. This may initially seem advantageous as it results in a "cleaner" engine operation, and the oil is regularly changed.

However, these deposits might restrict the piston's seal within the cylinder, leading to reduced compression and, as a result, a decrease in engine power. Additionally, the detergent additives in premium fuels can eliminate impurities, potentially harming the fuel injectors.

Adam Lehnort strongly recommends against using high-octane fuels in engines that lack a knock sensor, primarily concerning vehicles from the 1990s and earlier.

In conclusion, the expert suggests chemical fuel additives as an occasional, more cost-effective alternative to continuously filling with premium fuels.