Patterns of Vehicle Misfueling in 1981 and 1982: Where, When, What Vehicles, and How Often?

Based on nationwide gasoline diary records of 5,000 families, an analysis was conducted of automobile misfueling (use of leaded gasoline in a vehicle designed for unleaded gasoline) trends in 1981 and 1982.

The gasoline diary data base and the data handling and analysis techniques are described. Overall trends in vehicle misfueling are given, focusing on 1982 data, followed by more detailed information on the location and frequency of misfueling.

Conclusions are presented indicating that while variations exist in misfueling by region and vehicle age, overall misfueling is a widespread problem, because catalyst-equipped cars are increasing in number and age.