Buick 1993 Roadmaster Owner's Manual page 310

' X :
An Emission Control Service.
TheU.S. Ehyironmental Protection Agency has determined that the failure to perfo- this maintenance itein will not nullify the emission warranty or limit recall liability prior to thecompletion of vel&cle.
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useful Iife. Geneial Motors, however,.urges that all recommended maintenance services be performed.at the indicated intervals and the maintenance be recorded in "Section E:Maintenance Record".