Coia graduated from Glasgow University before going into hospital radio and eventually getting a job as a disc jockey at Radio Clyde.
In the early 1980s he also worked as a continuity announcer for Scottish Television and was the first voice on Channel 4. Subsequently he became a presenter of BBC1's daytime magazine programme, Pebble Mill.
In 1989 Coia became the host of the gameshow Catchword, and has since presented a number of other quizzes on various satellite and cable channels.
He stood in once with his wife, Debbie Greenwood, for Gloria Hunniford's afternoon chat show on Channel Five.