CLEMSON, S.C. — Georgia Tech coach Paul Johnson wasn’t sure where to start with his team’s offensive problems, much less how to begin fixing them. The Yellow Jackets (2-4, 0-3 Atlantic Coast Conference) have followed a 2-0 start with their first four-game losing streak since 1996. And they did it with the lowest rushing total of Johnson’s eight-season tenure, a team that came in averaging 311 yards on the ground held to 71 by the sixth-ranked Tigers in a 43-24 defeat Saturday.