Vancouver started the season strongly but was eliminated from the playoff race with a 3-2 loss to the Colorado Rapids on Oct. 19.
The Whitecaps rebounded to beat Colorado 3-0 in Sunday's regular-season finale, with Brazilian forward Camilo Sanvezzo getting a hat trick to win the MLS Golden Boot as the league's top scorer. But it wasn't enough to save Rennie's job.
Whitecaps president Bob Lenarduzzi said the club's inconsistency over the past couple years was problematic.
He said, "If we look back over the two years, we had two relatively good starts, and in each of those seasons we seemed to tail off."