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Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast
Check out The Fuel Pulse Show Podcast

Ethanol Fuel Problems


Ethanol Problems

We are long past the point where we're talking about ethanol gasoline as a new thing. Ethanol is a fact of life now with 10%-15% ethanol blends having been commonplace for a number of years. The renewable fuels mandates that are the legislative foundation for all the ethanol and biodiesel in our nation's fuel supply are aimed at improving air quality and reducing air pollution from fuel emissions. But for all its good points, ethanol fuels are associated with certain problems, whether for consumers, (who face loss of mileage and a tendency for ethanol to corrode plastic and fiberglass tanks and parts) or businesses (who face ethano phase separation problems in storage).

Why We Have Alternative Fuels And Oxygenates

Finding a gas station without at least 10% ethanol in their gasoline is nearly impossible in many states, evident from the warning stickers on most pumps. While there are fewer than 8,000 stations in North America offering ethanol-free gasoline, the prevalence of ethanol-blended options outweighs non-ethanol stations.

Though often misunderstood, ethanol serves as an "oxygenate," enhancing the fuel's oxygen content and consequently improving exhaust emissions' cleanliness and environmental impact. This ethanol inclusion in gasoline exemplifies the government's role in steering the free market towards alternative fuels, as permitted by the Clean Air Act. 

Key pieces of legislation played a crucial role in shaping alternative fuel adoption. The 1980 Synthetic Fuels Act, introduced during President Carter's tenure, aimed to reduce US oil dependence. However, it lost momentum as oil prices plummeted in the 1980s, only to regain prominence when fuel costs surged. That's tended to be the way it goes. When gas prices are low, people haven't historically been as concerned.

Subsequent legislation bolstered the movement. The 1988 Alternative Fuels Act mandated government agencies to purchase alternative-fuel vehicles and incentivized automakers to produce such vehicles. The 1990 Clean Air Act empowered the EPA to enforce mandates promoting better air quality through alternative fuels. The 1992 Energy Policy Act aimed for non-petroleum alternatives to comprise 30% of the fuel market by 2010.

These developments set the stage for significant changes in fuel supply by 1992. MTBE, used in the 1970s as an anti-knock agent, began blending into gasoline to reduce emissions. However, evidence emerged in the late-90s linking MTBE to health risks and groundwater contamination, leading to its market withdrawal. Ethanol, displacing MTBE, emerged as the primary oxygenate to meet EPA emissions standards. Though MTBE persists in "off-road" gasoline in some states, its use in highway vehicles has largely ceased.

The Good – Ethanol Advantages

Lower Emissions

Ethanol blended into gasoline offers advantages, particularly in reducing emissions. This benefits the environment and aligns with EPA goals. Gasoline blended with 10-85% ethanol produces lower carbon monoxide, unburned hydrocarbons, particulate matter, and harmful aromatic compounds (linked to cancer) when burned in engines. These benefits contribute to improved air quality and reduced pollution, especially in urban areas facing smog issues. For areas struggling with federal air quality standards, there's a financial incentive to address this problem, as non-compliance could lead to the loss of essential federal funds. 

Higher Octane

Oxygenates like ethanol and MTBE already had historical use before the 1992 Clean Air Act as octane improvers. Pure ethanol has an octane rating of 113, while E10 blends have the octane rating listed at the pump, which is usually the same as regular or premium gasoline. Unfortunately for the consumer, it is likely because, despite the ethanol additive having a high octane rating, the fuel blender uses a lower octane base gasoline in order to end up with the same octane rating in the E10 blend as they had before. So the consumer doesn’t really get an added octane benefit in an E10, despite the ethanol fraction having a higher octane rating.

Renewable Fuel

Ethanol is made in the United States from corn (in Brazil it is made from sugar cane), making it a renewable fuel that reduces (somewhat) our dependence on oil imports. This is a big plus for a lot of people who want to go more “green”.

Flex-Fuel Vehicles

These are vehicles that have had engine modifications to enable them to run on either gasoline or a high concentration of ethanol like E85. Putting such a high concentration of ethanol in an engine that has not been modified is never a good idea – flex-fuel vehicles have special fuel sensors to properly read the ethanol-fuel mixture and special fuel injection changes to ensure the mixture isn’t too rich or lean. Without these modifications, the vehicle won’t run right and you can very easily get a damaged engine over time.

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The Bad – Ethanol Problems For Consumer

Loss Of Mileage

Ethanol-blended fuels experience reduced mileage due to ethanol's lower energy content compared to gasoline. Gasoline molecules contain more carbon bonds, providing higher energy potential than smaller ethanol molecules. Pure ethanol has 35% less energy value than an equivalent amount of gasoline. However, most cars can't run on high ethanol concentrations (over 15-20%) without risking engine damage, as adjustments are needed for differing combustion properties. The common E10 blend contains only 10% ethanol, resulting in an energy value drop of around 3.5%-5.0%.

In October 2010, Congress authorized an increase from 10% to 15% ethanol levels, causing even larger fuel mileage reductions. But those changes haven't necessarily stuck nationwide. E10 is still the most common E-blend you'll find.

Water Attraction

Ethanol's exceptional water-absorption ability is crucial to understand. Even the purest ethanol available isn't 100% pure due to its affinity for water. This trait poses more significant challenges for marine users of E10-E85 fuels than for on-road drivers. Water, being heavier than fuel, accumulates at the tank's bottom, causing a range of fuel-related problems for engines of all sizes that use ethanol.

Breeding Ground For Microbes

Microbes like bacteria and fungi all need an accumulated water phase in order to grow and thrive in a fuel storage tank. The bacteria live in between the water and fuel, feeding off of both materials, growing and multiplying, and giving off the harmful by-products of their life cycle. If an infestation takes hold, problems with corrosion, filter plugging, and reduction in fuel quality can follow. However, ethanol blends, like gasoline, tend to be used quicker than stored diesel fuels, so this is not so much of a problem in actual practice for end users. But it is a concern for fuel handlers, refiners, and distributors, many of whom have to use millions of dollars a year of biocide to keep the problems in check.

Phase Separation

Phase Separation means the ethanol ‘phase’ separates from the gasoline ‘phase’ and results in two layers of two different compounds, instead of a homogenous mixture of gasoline and ethanol. At this point the ethanol will sink below the gasoline phase and mix with any more accumulated water, making an ethanol-water phase mixture that sits on the bottom of the tank where the fuel pickup line locates. Ethanol fuel that has phase-separated cannot be put back together because the ethanol and water have combined into a seamless layer. But that’s the least of the worries when this happens. You can have...

Loss Of Octane

When ethanol separates from gasoline, it causes a loss of 2-4octane points in the fuel mixture; in effect, as it separates, it drags the octane value of the gasoline by dissolving some of the organic fuel molecules that normally contribute to the octane rating of fuel. Those important molecules leave with the ethanol-water and the octane rating of the remaining gasoline drops to an unsatisfactory rating. An 87-octane fuel that separates can have its octane rating drop to 83-84, which is unsatisfactory for most vehicles and will cause performance issues.

Potential For Equipment Damage

An ethanol blend that has separated will have the ethanol and water mixture settled at the bottom of the tank, where the fuel line is. The fuel line potentially can suck this mixture up into the combustion chamber, where it will burn like an overly lean mixture (lean = not enough gasoline). Because it is not mostly gasoline now, burning this kind of fuel gives the real potential for valve damage. This becomes an expensive proposition.

Oxidation And Deposit Buildup

Water is one of the impurities that will accelerate oxidation reactions in any petroleum-based fuel, whether gasoline, diesel, biodiesel, or ethanol blends. Oxidation reactions are responsible for fuel stratification and the fallout of heavy ends from the fuel mixture. These heavy fuels can build up in the bottom of a fuel storage tank, and when they are injected as fuel, they do not burn like pure fuel but will leave deposits in all parts of the combustion system–combustion chamber, valves, and fuel injectors. At best, you get raised emissions to the catalytic converter, rough running, and poor engine performance, while at worst you get a drop in mileage.

Ethanol Solvency

Boat owners in the northeast can readily testify how ethanol blends up to E85 attach and dissolve rubber and plastic parts, even fiberglass fuel tanks. Ethanol has always been an excellent solvent and unfortunately, this is not a good thing for engines and fuel delivery systems that rely on rubber and plastic parts for their function. Repeated exposure over time will cause the plastic resins to dissolve in the ethanol; they subsequently build up as new deposits on valves, causing the same kind of performance issues as carbon deposits can.

Combating Ethanol Issues In Fuel

All of this is well and good, to know what the problems are. But we all want to know how to fix and prevent these problems. What can you do about them?

Bell Performance has been manufacturing custom fuel treatments for ethanol and other fuels for years. Consumers relied on Mix-I-Go for decades as a multi-function treatment for gas and ethanol that cleaned engines, restored mileage and prevented ethanol problems like water accumulation.

In May of 2012, Bell Performance went a step further with a new formulation called Ethanol Defense, which was designed to provide the same benefits of mileage improvement, detergency, and protection against ethanol damage that consumers are demanding, but all of this is also combined with a more robust water controlling power.

Consumers are demanding fuel treatments that work and put money back in their pockets. They don't want snake oil. They want performance and they want results. Bell Performance has been around for well over 100 years because the Bell Performance company makes problem-solving fuel treatments that do what they promise. Ethanol Defense makes the next generation of fuel treatment from Bell Performance.


Becoming more eco-friendly comes with a trade-off for consumers as ethanol blends pose challenges for vehicles and boats. The EPA's increase of ethanol to 15% in on-road gasolines amplifies these issues, creating a market for additives to counter them.

Some are superior to others. Top ethanol additives include mileage-improving combustion enhancers, detergents to cleanse deposits, water control agents, and safeguards against ethanol's effects on rubber and plastic parts. Be cautious of extravagant claims and guarantees; if something sounds too good to be true (like a 35% mileage boost), it likely is.

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