Born in Houston on Sept. 5, 1921, to the son and daughter of Italian immigrants from Sicily. He went to Harvard Business School on the G.I. bill, then returned to Humble Oil’s advertising department, where he helped its Texas gas stations jump from fifth to first in sales through a “cleanest restrooms” campaign. He co-founded an advertising agency in 1952, with a rival oil company, Conoco, as its first client. In 1966 Mr. Valenti took his talents for personal politicking — and lionizing his bosses — to Hollywood, heeding the request of Lew Wasserman and Arthur Krim, then chairmen of MCA/Universal and United Artists respectively, that he take over the Motion Picture Association. Mr. Valenti, who was four days shy of 83 when he stepped down from the motion picture association, continued to come to work, nattily dressed, long afterward