Is it Okay to Mix 87 and 89 Octane Fuel in Your Car?

The octane rating of gasoline is a measure of its ability to resist knocking or pinging during combustion. This resistance is crucial for engine performance and longevity. Many car owners wonder if it is alright to mix 87 and 89 octane fuel in their vehicles. This guide aims to clarify the situation and provide insights for car owners.

Understanding Octane Ratings

Octane ratings, such as 87 and 89, are crucial in determining the fuel's suitability for a car's engine. 87 octane is a common grade, often referred to as regular, while 89 octane is usually a higher grade, known as premium. These ratings refer to the fuel's resistance to pre-ignition, which can cause engine knocking and reduced performance.

Is Mixing 87 and 89 Octane Fuel Okay?

Generally, it is safe to mix 87 and 89 octane fuel in your car. When you mix the two, the resulting fuel will have an octane rating between 87 and 89. However, it is crucial to check your car’s owner manual and understand your car’s fuel requirements. Manufacturers often specify the recommended octane rating for optimal performance and engine health.

Considerations for Mixing Fuels

If your car is designed to use premium fuel, such as 91 octane or higher, using 87 octane fuel can lead to knocking or reduced engine efficiency over time. However, if your car is designed to use 87 octane fuel, mixing in 89 octane occasionally will not cause any significant issues. These mixed fuels blend well within the tank and burn effectively in the engine.

Manufacturer Recommendations

Each car is different, and it's essential to follow the manufacturer's recommendations. Many cars are designed to run on regular fuel (87 octane) and will perform well with a blend of 87 and 89 octane. This is because the engine is calibrated to handle a range of octane ratings. Mixing these fuels can be beneficial, as it can save you money while maintaining your engine's health.

Real-World Scenarios

Imagine you're driving through a station that only has 89 octane, but your car requires 87 octane. Instead of heading to the next station, you might fill up with a mix of both. This is perfectly fine, and it's a common practice. However, if you already have 89 octane in your tank, adding 87 octane won't solve any issues and might not provide any additional benefits.

Moreover, in places like Portland, Oregon, where fuel options can be diverse, some cars are designed to be as versatile as a local cafe, accommodating any fuel type. Others might be more particular, requiring a specific octane grade. Understanding your car's needs is paramount to ensure optimal performance and longevity.

Conclusion

While mixing 87 and 89 octane fuel in your car is generally safe, it's crucial to follow your manufacturer's recommendations. If your car is designed for 87 octane, mixing in 89 occasionally won't cause any issues. This flexibility can save you money and ensure your engine runs smoothly. Always check your owner's manual and pay attention to your car's specific needs.