Gasoline is not one thing, as many people may think. Refiners blend several components to produce the fuel we use. Gasoline is a mixture of petroleum, naphtha, ethanol, detergents and several other components. Occasionally we may have compatibility issues, between the ingredients. The recent problems in the Baton Rouge area remind us that nothing is perfect.
The symptoms of a gasoline problem
When blending several chemicals, an accounting for every possible interaction is difficult. Gasoline refineries do a great job and produce millions of gallons of problem free fuel. In mid March 2014 something did not go as planned. After filling their tanks, some drivers noticed the vehicle was harder to start. Others have check engine lights and run roughly. A few may refuse to start at all. The problem is an interaction within the fuel. The problem is noticeable when the engine is cold and may go away after running. This is because full fuel management does not take place until the oxygen sensors reach operating temperature.
The degree of the problem
The degree of the problem varies, depending on several factors. For instance, an engine in excellent condition may have fewer problems than an engine not maintained as well. Design of the engine is also a factor. Some flex-fuel ready vehicles may have no problem at all. Another factor may be how much fuel is added. For instance, filling a tank that is not empty, may have less effect than filling an empty tank. In the worse cases, the engine may not start.
Repair, when needed
The repair needed varies, depending on the symptoms. Many vehicles will clear up on their own, once we burn and replace the fuel. We have had great results on others, by chemically cleaning the valves. This process helps remove any contaminant that could cause the engine valves to stick. Test-driving the vehicle after cleaning shows that it has no symptoms.
We have seen no long-term problems and additional damage is very improbable. Draining the fuel tank is rarely necessary. A better plan is to simply dilute the fuel. We do this by running the tank down and adding 1/4 tank several times. By continuing to dilute the fuel with fresh, we can use the fuel in the tank and avoid unnecessary expense of disposal.
Some may try to take advantage
As with anything, there will be some who try to take advantage. View claims of engine damage and fuel system repair with skepticism. Seeking a second opinion when someone tells us the fuel has caused a major problem is wise. Many times the symptoms will go away on their own, once fresh fuel is added. Other times cleaning the valves helps speed the process. This service takes less than an hour and should be priced accordingly. Be suspicious if expensive repair is recommended as a result of the fuel.
They produced most of the suspected gasoline at the Baton Rouge Exxon refinery, possibly in two batches. Exxon also produces fuel for several other companies. This does NOT mean the fuels are all the same. They blend each to the specifications of their brand and it is a unique product. The Exxon brand may have additives to increase mileage, clean the engine, prevent a carbon buildup and so on. A private label brand may have only the federally mandated minimum additives.