The game-winner came in the 59th minute when Lee Young-Pyo sent a pass into the penalty area for Daigo Kobayashi, who left it for Koffie to line inside the right post.
The Whitecaps (1-0-0) cruised the rest of the way to the victory.
TFC (0-1-0) fell in its first game under new head Coach Ryan Nelsen.
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