Van Dyke, a San Mateo resident, was hit around 6:15 a.m. on El Camino Real near state Highway 92.
One of the motorists involved, a 35-year-old San Francisco man driving a black Honda, remained at the scene, but the other driver drove away after the collision, San Mateo police said.
That second car, a white Toyota, was tracked down shortly after the collision and the driver, a 67-year-old San Mateo man, is said to be cooperating with police.
Police said they are investigating whether Van Dyke had come from a nearby homeless encampment. He was not in a crosswalk when he was struck, police said. A stretch of El Camino Real was closed after the accident, and the California Highway Patrol initially shut down all Highway 92 ramps in that spot.
All roadways were reopened by about 11 a.m.