Growing concerns about gasoline deposit-control additives will be addressed by the Environmental Protection Agency, Ward's has learned. A response is being developed under the direction of the EPA Assessment and Standards Div.

A supplier engineer says there is no question about the growth in problems he believes may be related to under-use of deposit-control additives — one industry source suggests 85% of all U.S. gasoline doesn't contain sufficient amounts because oil companies are cutting corners. Moreover, many cheaper additives actually increase engine deposits.

In an effort to move analysis of the problem and its solution forward, both auto maker trade associations, the Alliance of Automobile Manufacturers and the Assn. of International Auto Manufacturers, say they are seeking to arrange meetings with the EPA.

The American Petroleum Institute won't comment on the controversy, saying that the selection and dosage of gasoline additives for each brand and grade of fuel is decided by its member oil companies.

BP/Amoco says all grades of Amoco, BP and Arco gasoline contain full deposit-control additives that do not contribute to combustion chamber deposits — and that its Amoco Ultimate has sufficient additives to clean injectors and intake valves.