That is the all-time most popular Adam 12 episode according to the statisticians. It's called "The Search". For you continuity buffs, watch how Malloy is chasing the bad guys in a '71 Plymouth Satellite, and then "rolls" a '68 or '69 Satellite....
here's a link to the episode:
http://www.hulu.com/watch/46164/adam-12-the-search