What car was John F. Kennedy riding in when he was killed?

He was not driving. He was riding in a dark blue 1961 Lincoln Continental convertible.

The driver was Special Agent William Greer, US Secret Service. Agent Roy Kellerman, US Secret Service, was seated to his right. Behind Agent Greer was Mrs. Connally, with Governor Connally to her right. Mrs. Kennedy was behind her with the President to her right.

From Warren Commission report, pages 49-50.