Buick 1994 Roadmaster Owner's Manual page 289

The services shown in this schedule up to 48 000 miles (80 000 km) should be performed after
I
48 000 miles at the same intervals.
*
An Emission Control Service.
The U.S. Environmental Protection Agency or the California Air Resources Board has determined that the failure to perform this maintenance item will not nullify the emission warranty or limitrecall
liability prior to the completion of vehicle useful life. General Motors, however, urges that all recommended maintenance services be performed at the indicated intervals and the maintenance be
recorded in "Section EMaintenance Record".
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