When the strangler is applying make up to the first victim, her eyes are twitching, showing that she is still alive.
The car wash in the show is advertised on a sign as the "King Street Car Wash ($1.75)", but Danno later refers to it as "Frank's Car Wash and Filling Station."
When Cathy is struggling with her attacker and tries to get to the telephone, the camera person's hand is clearly visible on the right-hand side of the screen. The hand is so close to the camera that it makes the fingers look enormous.