Continuity: In The pilot episode, both Starsky and Hutch jump/fall into a swimming pool. A close-up of Starsky in the water shows him in his blue shirt without his sweater, and his gun in his right hand. But the next cut to him shows him standing up out of the water with his sweater back on, and his gun in his left hand.
Revealing mistakes: The Ford Torino was an automatic, yet Starkey's car always had the very obvious sound that could only be made by a standard (or stick) shift.