How To Test E85

If you own a flex-fuel vehicle or are considering using E85 fuel, it is crucial to know how to test it. Testing your E85 fuel ensures that it meets the standards and is safe to use in your vehicle.

This article will guide you through the process of testing E85 fuel, from understanding its composition to interpreting the results and making informed decisions.

To test E85 fuel, you need to be equipped with certain knowledge and tools. This article will provide you with everything you need to know about testing E85 fuel and give you the confidence to ensure that your fuel is of good quality.

With this knowledge and the right equipment, you will be able to take control of your vehicle’s fuel quality and ensure its longevity. So, let’s get started!

Understand the Composition of E85

You’ll need to understand what makes up E85, including the percentage of ethanol and gasoline, in order to properly test it.

E85 is a fuel blend that contains up to 85% ethanol and 15% gasoline. Ethanol production is typically derived from corn, sugarcane, or other crops that can be fermented and distilled.

It’s important to note that E85 has a lower energy content than gasoline, which means that vehicles using E85 may experience decreased fuel economy. However, the use of E85 can have a positive environmental impact, as ethanol is a renewable resource and produces fewer greenhouse gas emissions compared to gasoline.

Understanding the composition of E85 will allow you to properly test the fuel for its efficiency and environmental benefits.

Gather the Necessary Equipment

To properly test the composition of E85, you’ll need a fuel testing kit. The kit should include a hydrometer, thermometer, and graduated cylinder. It’s important to wear protective gear, such as gloves and safety glasses, when handling fuel and testing equipment.

Make sure you have all the necessary equipment and protective gear before beginning the testing process. This will ensure accurate and safe results.

Fuel Testing Kit

Using a fuel testing kit can provide valuable insight into the quality and composition of e85. These kits are cost-effective alternatives to more expensive laboratory testing. They allow you to test for important parameters such as ethanol content, water content, and pH levels in a matter of minutes.

Common mistakes when using fuel testing kits include failing to follow the manufacturer’s instructions, using expired or contaminated testing solutions, and not properly calibrating the kit. It’s important to take the time to read the instructions carefully and to use fresh testing solutions. Additionally, you should regularly calibrate your kit to ensure accurate results.

By using a fuel testing kit correctly, you can ensure that the e85 you’re using is of high quality and safe for your vehicle.

Protective Gear

Make sure you’re safe and protected while handling e85 by wearing proper protective gear. Choosing appropriate gear is crucial for your safety.

Start by wearing gloves that are resistant to chemicals, such as nitrile or neoprene. These gloves will protect your hands from coming into direct contact with e85, which can cause irritation or even chemical burns.

Another crucial piece of protective gear is eye protection. Wear safety goggles to prevent e85 from splashing into your eyes.

If you’re working with e85 in an enclosed space, make sure to wear a respirator to avoid inhaling any fumes.

Remember, safety precautions during testing are essential to safeguard yourself and others around you. By wearing appropriate protective gear, you can ensure a safe and successful e85 testing experience.

Perform a Visual Inspection

Before testing E85, it’s important for you to perform a visual inspection to ensure the quality of the fuel.

Check for any water or sediments in the fuel as this can cause engine damage. Additionally, observe the fuel for any unusual colors or odors which can indicate contamination.

By performing a thorough visual inspection, you can ensure accurate testing and prevent any potential damage to your engine.

Check for Water and Sediments

Don’t let water and sediments ruin your engine – always check for them before using E85. These contaminants can affect the performance of your engine and cause costly repairs. To prevent contamination, make sure to store your E85 in a proper container, away from moisture and dirt.

To check for water and sediments in your E85, use a clear container and fill it up to about half. Let it sit for a few minutes and observe the bottom of the container. If there are sediments or water droplets, it’s best to dispose of the fuel and not use it in your engine.

You can also use a water-finding paste to check for water in the fuel. This paste changes color when it comes in contact with water, indicating the presence of water in the fuel.

By taking these simple steps, you can ensure that your engine runs smoothly and avoid any unexpected repairs due to contaminated fuel. Remember, prevention is always better than cure.

Observe for Unusual Colors or Odors

Keep an eye out for any strange colors or smells when using E85 in your engine – these could be indicators of potential issues that need to be addressed.

E85 should have a clear, yellowish appearance and a slightly sweet odor. If you notice any unusual colors, such as a cloudy or dark appearance, or odors that are off-putting, it may be a sign of contamination or degraded fuel.

Identifying potential hazards early is crucial to maintaining the health and performance of your engine. If you notice any unusual colors or odors when using E85, it’s important to seek professional assistance.

A mechanic or fuel specialist can help determine the cause of the issue and provide guidance on how to address it. Don’t ignore any signs of trouble – taking action quickly can help prevent costly repairs down the line.

Conduct a Chemical Test

To conduct a chemical test on your E85 fuel, you’ll need to measure its ethanol content and determine its octane rating.

To measure ethanol content, you can use a hydrometer or a refractometer.

The octane rating can be determined through a knock test or an octane rating engine.

By performing these tests, you can ensure that your E85 fuel meets the required standards for optimal engine performance.

Measure the Ethanol Content

Measuring the ethanol content in E85 is essential, as it determines the fuel’s performance and efficiency. Ethanol sources can vary, affecting the fuel’s composition and potentially leading to engine damage.

To measure the ethanol content, a handheld ethanol tester can be used. Simply insert the tester into the fuel and wait for a reading. The tester will provide a percentage of ethanol in the fuel, which should ideally be between 70-85% for optimal performance.

E85 benefits can only be fully realized if the ethanol content is properly measured and maintained. Regular testing can help ensure that the fuel meets these standards and avoid potential engine damage.

Determine the Octane Rating

Now that you know how to measure the ethanol content of your e85 fuel, it’s time to move on to determining its octane rating. This is important because the higher the octane rating, the more resistant the fuel is to knocking or detonation, which can damage your engine.

One way to boost the octane rating of e85 is by using octane boosting additives. These additives work by increasing the fuel’s resistance to knocking and improving its combustion efficiency. However, it’s important to note that not all additives are created equal and some may even have harmful effects on your engine.

Additionally, alternative octane rating methods such as the Motor Octane Number (MON) and Research Octane Number (RON) can also be used to determine the fuel’s resistance to knocking. These methods take into account different factors such as engine speed and load, and can provide a more accurate measurement of the fuel’s octane rating.

Interpret the Results

Now that you’ve conducted a chemical test on your e85 fuel, it’s time to interpret the results.

Your first step is to compare the results with standard specifications for e85 fuel. If the results fall within the acceptable range, then you can adjust your fuel mixture accordingly.

However, if the results are outside of the accepted range, you may need to make some changes to your fuel source or adjust your fuel mixture to ensure optimal performance.

Compare with Standard Specifications

Comparing E85 with standard specifications is crucial to ensure its quality and suitability for use in vehicles. When testing E85, it’s important to compare the results with standard specifications provided by organizations such as ASTM International. These specifications outline the requirements for the chemical composition, physical properties, and performance characteristics of E85.

One aspect to compare is the price of the E85 being tested with the market average. If the price is significantly lower, it may be an indication of lower quality or a higher ethanol content, which can negatively impact vehicle performance.

Evaluating the efficiency of the E85 is also important as it can affect fuel economy and engine performance. By comparing the results with standard specifications, you can determine if the E85 meets the necessary requirements for use in vehicles.

Adjust Fuel Mixture Accordingly

To ensure optimal performance, you should adjust the fuel mixture of your vehicle accordingly when using E85. This is because E85 has a higher oxygen content than regular gasoline, which means that it requires more fuel to be burned in order to produce the same amount of power.

As a result, your engine may run lean if you don’t adjust the fuel mixture, which can cause damage over time. There are several adjustment techniques you can use to optimize fuel efficiency when using E85.

One approach is to install a flex fuel sensor, which will automatically adjust the fuel mixture based on the percentage of ethanol in the fuel. Another approach is to manually adjust the fuel mixture using a fuel management system, such as a piggyback ECU or a standalone ECU.

By adjusting the fuel mixture, you can ensure that your engine is running at its optimal performance level and that you’re getting the most out of your fuel efficiency.


In conclusion, testing E85 is essential to ensure its quality and suitability for use in your vehicle. It’s important to understand the composition of E85, gather the necessary equipment, and perform a visual inspection. By following these steps, you can rest assured that the E85 you’re using is of high quality and free from any contaminants.

Furthermore, interpreting the results of your chemical test is equally important. This will provide you with valuable information about the ethanol content, water content, and any impurities present in the E85. Regularly testing E85 is recommended to ensure that it meets the required standards for use in your vehicle.

By doing so, you can avoid any potential engine damage and ensure the optimal performance of your vehicle.