Eric Dickerson had his most rushing yards in a game versus the Houston Oilers on December 9, 1984, with 215 yards.

eric dickerson most rushing yards in a regular season game
12/9/1984Dickerson11/4/1984Dickerson10/5/1986Dickerson10/2/1983Dickerson12/27/1987Dickerson9/7/1986Dickerson9/25/1983Dickerson11/25/1984Dickerson10/14/1984Dickerson10/26/1986Dickerson12/4/1988Dickerson10/23/1988Dickerson12/18/1988Dickerson10/31/1988Dickerson11/15/1987Dickerson10/22/1989Dickerson11/24/1985Dickerson9/23/1985Dickerson9/13/1987Dickerson12/2/1984Dickerson11/11/1984Dickerson11/14/1983Dickerson10/22/1984Dickerson215208207199196193192191175170169169166159154152150150149149149146145
Results may be incomplete. StatMuse has complete game-level data for rushing yards going back to the 1960 season.