Can You Mix Ethanol And Non-Ethanol Gas In A Car?

The automotive industry is constantly evolving, giving birth to numerous gas types. With the availability of various options on today’s market, many drivers question whether mixing no-ethanol gas vs ethanol in their vehicles is safe and acceptable. Dive into this article to dispel common misconceptions and make an informed choice at gas stations.

Ethanol Vs Non-Ethanol Gas: What Are The Differences?

True to their name, ethanol and non-ethanol gas feature distinct chemical compositions. The former is a liquid derived from sugar cane or corn grain, going through fermentation and distillation. Ethanol gas has various variants, including E85, E15, and E10. The number followed by the letter “E” represents the percentage of ethanol content when mixed with gasoline.

On the other hand, non-ethanol gas is produced from petroleum without any additives. Their distinct composition sets the stage for differences in their properties as listed below:

Gas mileageLower (On average, it reduces the gas mileage by 3%)Higher
Corrosion-resistancePoor (can cause corrosion)Don’t cause corrosion
Shelf lifeShort (~ 3 months)Long (~ 6 months)
Production & transportation costCheapExpensive
AvailabilityPopularLess popular

Can You Mix Non-Ethanol Gas With Regular Gasoline (Ethanol Gas)?

Yes, you can mix non-ethanol and ethanol (regular) gas, thanks to a minor difference in chemical composition. Most modern vehicles are designed to handle a blend of the two types safely. In fact, there is at least 10% of ethanol in gasoline sold in the US.

That said, the mixture of ethanol and non-ethanol gas is not the best practice. This habit may increase emissions and fuel consumption. Instead, stick to the fuel option recommended for your specific vehicle to ensure optimal performance.

mixing gas

However, if you accidentally put non-ethanol gas in your car, do not panic. It is unlikely to cause any immediate or severe damage to your cars.

Potential Risks Of Mixing Ethanol And No Ethanol Gas

Decreased Gas Mileage

Ethanol has a lower energy density than gasoline, meaning it contains fewer BTUs (British Thermal Units) per unit of volume. As a result, vehicles running on ethanol-blended fuel may experience a slight decrease in fuel efficiency compared to using non-ethanol gas alone.

Fuel System Corrosion

Remember that ethanol is a form of alcohol that can dissolve rubber and plastic. If you use ethanol gas for an extended time, the substance can corrode critical components such as gaskets, rings, fuel lines, etc.

Fuel System Corrosion
Fuel System Corrosion

As a result, your vehicle will suffer from leaks or clogged filters. Regardless of the situation, it hinders the engine’s performance, leading to serious damage.

Environmental Pollutions

Using solely ethanol gasoline can cut down on certain harmful emissions, such as carbon monoxide and greenhouse gasses. However, mixing it with the non-ethanol type will result in different characteristics. Depending on the specific ratio, the amount of released carbon and other harmful agents increases, leaving serious consequences for the environment.

Engine Damage

Using blended fuel can affect your car’s health in the long term, particularly if it is designed to run on a certain type of fuel. Most mechanics do not recommend blending non-ethanol and ethanol gas for older cars, as they might not be able to handle renewable biofuel.

Tips To Minimize Risks When Mixing The Two

If you are considering mixing ethanol and non-ethanol gas, here are some tips to keep in mind:

Check your vehicle’s compatibility

Most modern vehicles, especially those manufactured since the late 1980s, are compatible with E10. However, referring to your vehicle’s owner’s manual is always a good idea, or contact the manufacturer to verify the recommended fuel types and the accurate ratio for your car.

Start with a small amount

Start with a small portion of ethanol first and gradually increase the blending ratio. This approach allows you to observe any potential effects on the overall performance, fuel efficiency, and emissions to adjust the ratio accordingly.


Is Ethanol Free Gas Good For Your Car?

There is no perfect choice, and ethanol-free fuel is no different. Consider its advantages and disadvantages for making better decisions.


  • It boosts fuel economy
  • It minimizes potential harm to your engine
  • It has a longer lifespan


  • It releases more pollutant gasses to the environment
  • You must pay a higher price
  • It is not always available at all gas stations

Is Ethanol In Gas Good Or Bad?

Similar to its counterpart, ethanol gas has two sides.


  • It is environmentally friendly
  • Users can save on their gas cost


  • It may cause corrosion to fuel system components
  • It reduces fuel economy

Can Any Car Use Ethanol-Free Gas?

Not all cars are designed to use ethanol-free gas. Several old models cannot operate smoothly with this fuel type, such as:

  • Ford Focus 2002 – 2004
  • Suzuki Cars 2008 and earlier
  • Mazda 3 and 6 before 2005
  • Audi A3 from 2000 and before


For most modern vehicles, mixing ethanol and non-ethanol gasoline is generally safe. Still, it is worth noticing the risks and considering your vehicle’s compatibility. 

Remember that certain older or specialized models may have specific requirements. It is always recommended to consult your owner’s manual or contact the manufacturer to determine the suitable fuel for your car.

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Alex Lewis

Alex Lewis

Petroleum Engineer At Rex Energy

I have worked in a variety of roles and professions, from quality engineering in the automotive industry to production engineer in the oil and gas sector. From a technical point of view, these roles have shown me how to design a process, ensure it is efficient and up to standard, and manage the execution of the said process from start to finish.

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