Fuel system failure

Ethanol (ethanol msds) is a much stronger solvent than gasoline. It also absorbs water. Can you think of one component in your fuel system that is susceptible to solvents and shouldn't dry out? That's right, your seals and gaskets.

Ethanol can quickly dry out and destroy rubber fuel system components, including gaskets and hoses. Some are designed for ethanol, but most are not, and ethanol concentrations as low as 15% destroy them quickly. This means there is no E15 in your conventional vehicle.

Water problem

The hygroscopicity of ethanol is the cause of many problems, including engine problems. On cold days, condensation that forms inside the tank is usually inconsequential, but the presence of ethanol draws all the water into the fuel.

This can cause a variety of problems with the engine, including dirt, corrosion, and knocking as the damage worsens.

The role of ethanol in flex-fuel vehicles

Some vehicles are designed to run on ethanol. These vehicles are often called "flex-fuel" by manufacturers. Flex fuel usually means one of two things. Vehicles are either designed for E15 (15% ethanol) or the more potent E85 (85% ethanol). These vehicles can take advantage of cheaper fuel without the risk of catastrophic damage that regular cars face.

Just to clarify: flex-fuel vehicles can safely use any percentage of ethanol they are certified for. Using low-ethanol gasoline, E10 or less, probably won't hurt them too much either.

Can an old car use ethanol?

In general, older cars should avoid using ethanol gasoline as much as possible. However, this dose can cause intoxication, while low levels of ethanol usually do not cause significant harm. Under the right circumstances, however, years of frequent use of ethanol can wear out old engines.

If you drive a classic car, especially one with leaded gasoline, avoid ethanol like the plague. Running these old engines on unleaded fuel is hard enough for the valve seat - dumping ethanol in the mixture is like hitting them with a hammer.