Do Not Mix Pertalite with Pertamax: Here’s the Impact

SOLO, KOMPAS.com — Mixing two grades of petrol with different quality levels, such as Pertamax and Pertalite, is commonly done by motorists in a bid to obtain better-quality fuel at an affordable price.

In fact, Pertamax and Pertalite are types of petrol produced by Pertamina, with different price points, characteristics and quality.

Pertamax has an octane rating (RON) of 92, slightly higher than Pertalite at RON 90. This difference affects the power produced by the engine.

“If mixed 50/50, it becomes RON 91, and neither petrol would meet its respective standard. As a result, combustion quality declines and engine performance can be affected,” Jayan told KOMPAS.com recently.

If a driver normally uses Pertalite, their vehicle’s engine performance is better. Conversely, if a driver normally uses Pertamax, the mixed fuel would be detrimental.

“If mixed, the formulation will be disrupted, resulting in more carbon deposits, which affects the combustion engine’s performance, so it is not recommended,” Tri told KOMPAS.com recently.

Hardi Wibowo, owner of a Nissan-Honda specialist workshop in Yogyakarta, said the reduced performance of the Pertamax-Pertalite mix is due to the residues produced.

Hardi said the data were obtained from observations of modern cars undergoing routine maintenance every six months at his workshop.

“We advise always using petrol as recommended by the manufacturer, at least RON 92; when below that, including if mixed, there is potential for reduced performance, such as knocking and the combustion chamber getting dirty quickly,” Hardi said.

“Petrol with a low RON tends to ignite on its own; this triggers knocking and the power produced becomes suboptimal, and it also makes the car require more frequent cleaning or maintenance,” Hardi added.

Thus, consumers are not advised to mix two different petrol types, as Pertalite’s properties will influence Pertamax, which better aligns with manufacturer recommendations.