Motorists passing up the corncob, but alcohol's still getting in the tank

Gasohol. Back in the ''oil crisis'' days of 1973 and '79 it got to be a pretty popular word. It seemed like a way for Americans to keep their cars fed, while they drove around thinking they had done their part to cut oil imports.

Now, in many parts of the United States, those corncob-decorated gasohol pumps may disappear as fast as gas lines in an oil glut.

''Gasohol, as a name, is dying,'' says Douglas Snyder, a spokesman for Archer-Daniels-Midland Company, of Decatur, Ill., the nation's largest producer of ethanol. Ethanol is the grain-derived product that makes up 10 percent of the gasohol mixture.

''But this doesn't mean that the idea of alcohol-enhanced fuels is fizzling, '' Mr. Snyder said.

What is happening, he and other experts say, is that instead of using ethanol to make gasohol, refiners are using it to boost the octane levels of regular and premium grades of gasoline. When used this way, the fuel contains less than the 10 percent ethanol required to call it gasohol.

Ethanol in fuel can raise the octane level by two to three points, said James Stearns, director of the office of alcohol fuels at the US Department of Energy. He added: ''Gasohol got very different receptions in different parts of the country.''

In the Midwest, where it is still being sold at some stations, motorists driving past cornfields have little trouble making a mental connection between the grains they see and the fuel they put in their car. In other regions, especially cities, the connection isn't so easily made. But most drivers, urban or rural, do know about higher octane and more power.

''We're no longer using ethanol as a fuel extender,'' said Marilyn Povodator of Texaco. ''We're using it as an octane booster.'' Soon, Texaco will have a lot more ethanol for its octane-boosting.

In a month or so, she said, an ethanol plant capable of producing 60 million gallons of ethanol a year will open in Pekin, Ill. The plant is a joint venture between Texaco and CPC International Inc., the Englewood Cliffs, N.J., company that makes products like Mazola corn oil, Skippy peanut butter, and Hellman's mayonnaise.

While most of the output from this ethanol plant will be used for increasing octane, some of it will find its way to the gasohol pumps at Texaco filling stations in four Midwestern states: Illinois, Indiana, Kentucky, and Missouri.

The Midwest may end up being the only part of the country with gasohol pumps. Texaco this week announced a halt to a two-year effort to sell gasohol in the Northeast. The test proved unsuccessful because of high shipping costs for the ethanol, the lack of state tax incentives, and the oil glut, Texaco officials said.

In August, the Amoco Oil Company announced a similar retreat, leaving itself in the gasohol business in just Iowa and Kansas. ''In those two states gasohol gets a significant tax break,'' said Amoco spokesman Michael Thompson. In Iowa, for instance, the tax on gasohol is 6 cents a gallon, compared with 13 cents for gasoline, a state Transportation Department official said. The lack of tax subsidies for gasohol means oil companies have to sell it for 5 to 8 cents more than premium gasoline, too stiff a price for most people.

''We're not at all surprised at what's happened'' to gasohol, said Gus Ensz of the American Petroleum Institute. With all the fuel needed to plow, sow, and harvest a field as well as transport the grain, he maintains, it takes two to three gallons of petroleum to make one gallon of alcohol for ethanol production. Some systems, however, produce more alcohol than the oil they consume, the experts say.

With Amoco and Texaco out of the gasohol business in all but six Midwestern states, most of the gasohol sold in the rest of the country is coming through small oil companies and ''jobbers'' who deliver occasional truckloads of the fuel to independent stations.

In New England, said Bob Kimmett of the Bay State Gasoline Retailers Association, ''the gasohol market has been very soft. . . . The product has lost a lot of its market share.'' Besides the higher costs, Mr. Kimmett said, gasohol also fell into disfavor because it can lead to clogged engine parts.

Like the alcohol in many home cleaning supplies, the alcohol in gasohol can act as a cleaning agent in a car's engine, removing sediment and film that build up as a natural part of the engine's life. These loose particles can then find their way to other car parts.

One motorist made this discovery with his 1975 Plymouth station wagon. After two tankfuls of gasohol, his engine began to stall and choke, and often it wouldn't start at all. A visit to his mechanic showed that the fuel loosened the film that had built up on the inside of his gas tank and hopelessly clogged the carburetor. Those two tanks of gasohol ended up costing the motorist an extra $ 145 for a new carburetor.

''This hasn't been a problem with newer cars, but older ones can have a lot of trouble,'' Kimmett said.

''We experienced few of these complaints from motorists about the product,'' countered Thompson of Amoco. In Amoco's tests, he said, gasohol was used as a replacement for lead-free premium, and in the newer cars that need lead-free fuel, clogging problems rarely occurred.