Premium fuels' false economy: Benefit or harm for your car?

Experts in the automotive industry point out that so-called premium fuels, often advertised as more efficient or sporty, are not always beneficial for cars. In the case of older vehicles, they may even cause more harm than good.

Gas stations promote more expensive variants as completely safe and exceptionally beneficial, but mechanics' opinions are divided. Studies conducted by the ADAC organization show that using the highest quality fuels can only reduce consumption by 1-5 percent.

As explained by the expert from the ProfiAuto Service network, Adam Lehnort, based on mechanics' experiences, specially refined fuels can cause damage. The cleaning additives present in them can remove deposits of accumulated contaminants, which then penetrate the engine oil. This may seem beneficial because the engine operates "cleanly," and the oil is regularly changed.

Only these deposits can limit the tightness of the piston in the cylinder, which leads to a decrease in compression and, consequently, to a reduction in engine power. What's more, detergent additives in premium fuels can wash out contaminants, which can then damage fuel injectors.

Adam Lehnort strongly advises against using high-octane fuels in engines without a knock sensor, mainly referring to vehicle models from the 90s and older.

Premium fuels contain so-called anti-knock additives, which are intended to prevent piston and valve burnout and even damage to the engine head caused by knock combustion. If the engine is not equipped with a knock sensor, fuel with an increased octane number may slow the combustion process.

In conclusion, the expert offers an alternative of chemical additives to fuel, which can be used occasionally as a more economical solution than continuously filling up with premium fuels.