In Terminator 2, why did the T1000 Calmly walk behind John Conner in the Steel Mill? Why didn't he sprint?

There are 2 scenes in the movie where the t1000 Sprints behind John Conner and the good terminator.. Both those scene's he is able to keep up with car's, at the end of the movie, uming he's been chasing Conner for a while and this is his 4th chance to kill him, why did he just patiently walk behind them? He had his chance to kill him, Sarah, and Probably the t800 because the t800 was pretty banged up. Yet instead he just patiently walks behind them while they run threw the steel mill and make plans. I don't understand this.