Karen Carlson, who played Christine Phelps was married to David Soul from 1968 until 1977. She had also appeared in Gillian (1976).
Karen Carlson's second and final appearance in the series. However, in 2018 she played Cora in the 15 minute short, S&H parody Sparky & Butch (2018) about two retired cops who still chase crooks and the ladies.
When Starsky and Hutch arrest the rapist at the construction site while Christine consoles the victim, from the heightened view of the Gran Torino you can see someone pop up in the back seat.