E10 gasoline does not affect engines

The Ministry of Industry and Trade (MOIT) has issued Circular 50, which sets out the roadmap for blending biofuels with conventional fuels in Vietnam.

Accordingly, from June 1, 2026, E10 will be used for gasoline engine nationwide, contributing to emission reduction commitments. In addition, E5RON92 gasoline will continue to be blended and used for gasoline engines until December 31, 2030.

Dang Tat Thanh, PhD, from the MOIT’s Department of Innovation, Green Transition and Industrial Promotion emphasized that switching to biofuels brings many other benefits, such as ensuring energy security, delivering significant economic benefits, contributing to environmental protection, and reducing greenhouse gas emissions by 37–84 percent. Moreover, using E10 gasoline also ensures engine safety. 

When drafting Circular 50, MOIT consulted many major automakers (Toyota, Honda, Ford, etc.) and technical organizations such as the Society of Automotive Engineers (SAE). These entities all confirmed that biofuels E5 and E10 do not harm engines. On the contrary, E10 has a higher octane rating, helping engines operate more efficiently and reducing knocking.

"Thus, it is clear that using E10 and E5 does not affect the engine and aligns with Vietnam's current green and clean trends," Thanh affirmed.

Some petroleum traders have already conducted trial sales of E10 and received positive feedback. After more than 5 months of pilot sales, Ho Ngoc Linh from Petrolimex stated that sales volume has increased, reflecting consumer acceptance. Regarding quality, Petrolimex has not recorded any complaints or negative feedback.

According to Nguyen Huu Tien, Deputy Director of the Department of Science, Technology, and Environment (Ministry of Construction), most gasoline engines currently in use can use E10 immediately without technical modification, which is a significant advantage.

“We have strengthened inspection and supervision, and test results show that E10 meets technical requirements,” Linh said.

According to Nguyen Huu Tien, Deputy Director of the Department of Science, Technology, Environment and Construction Materials (Ministry of Construction), most gasoline engines currently in use can immediately use E10 without modification or technical changes, which is a major advantage.

Therefore, the MOIT’s roadmap for transitioning to E10 is an appropriate and practical solution. The issue of concern now is the supply capacity and ensuring the quality of biofuel.

Lo Hai Nam from the Vietnam Association of Motorcycle Manufacturers (VAMM), also confirmed that the motorcycles from VAMM member brands can all switch to E10, including older models manufactured 20-25 years ago.

However, when using E10, if a vehicle is left unused for a long time, it may be harder to start compared with mineral gasoline, because biofuels have water-absorbing characteristics.

In addition, biofuels have cleaning properties. For fuel systems that use metal fuel tanks, deposits can build up over time; when biofuels are used, these deposits may be cleaned off and broken into small particles, which can cause clogging or make pumping and suction more difficult.

Therefore, manufacturers always recommend that users regularly inspect and maintain their vehicles’ fuel systems. If these recommendations are followed, such issues can be completely avoided, he said.

According to Associate Professor Dam Hoang Phuc, PhD, from Hanoi University of Science and Technology, the use of E10 has been around for a long time, so manufacturers have researched engine compatibility with this biofuel. Some vehicles even indicate E20 compatibility, meaning they can use E20 gasoline, as committed by the manufacturer. When opening the fuel cap and seeing markings such as “Euro 5 E20,” consumers can know which fuel is appropriate for their vehicles.

But the greatest danger is using the wrong standard level of gasoline, not because of the gasoline. Consumers should care and note whether the car they are driving needs to use Euro 3, 4, or 5. Only in this way can they protect their car and their wallet," Phuc said.

Ethanol is a solvent that does not affect mechanical details, only affecting non-metal materials such as gaskets, seals, and rubber. 

He stressed that vehicles need to be cared for and must have their fuel systems checked; that is a principle, even if E10 is not used.

For ethanol, because ethanol has cleaning properties, it can cause deposits in the fuel tank to dissolve more quickly and move through the fuel system toward the engine. However, in newer cars, fuel tanks and fuel systems have been improved, so deposit buildup rarely occurs.

Tam An