Factual error: The truck that the T-1000 uses to try and run down John in the overspill, is a Freightliner FLA 9664, which uses a diesel engine - it does not use petrol. Diesel is much harder to combust in comparison to petrol/gasoline, and the spark from the battery cables on the spilt diesel would absolutely never ignite under those circumstances. (00:37:55)
Terminator 2: Judgment Day (1991)
Plot summary
Directed by: James Cameron
Starring: Arnold Schwarzenegger, Robert Patrick, Xander Berkeley, Edward Furlong, Linda Hamilton
Two terminators, the T-800 & the T-1000, are sent from an apocolyptic future back to Los Angeles, 1991. The T-800 is reprogrammed as a protector to John Connor, the future savior of mankind, who is currently living with foster parents. Sarah, his mother, is locked up in the Pescadero Mental Hospital. The T-800, John, and Sarah flee from the seemingly unstoppable T-1000. They are joined by Miles Dyson, a computer programmer/technician who is inadvertently responsible for the rise of the machines. Together the four break into Cyberdine Systems in an attempt to destroy the technology and stop the war from occuring.
More mistakes in Terminator 2: Judgment Day
John Connor: We've got company.
Miles Dyson: Police?
Sarah Connor: How many?
John Connor: Uh, all of them, I think.
Trivia: The minigun that the Terminator (Arnie) uses in the Cyberdyne scene was so heavy that Arnold Schwarzenegger was the only person on set strong enough to lift it.
Upvote valid corrections to help move entries into the corrections section.
Suggested correction: In one of the special features on the Blu-ray version, director James Cameron can be seen holding and shooting the minigun, while saying: "Arnold's gonna love this."
Question: Arnold said that when the T-1000 took the form of someone he would likely terminate the person being copied. Why didn't the T-1000 kill Sarah? He had been in physical contact and could mimic her voice. There was no reason to get her to call John at the end, he could have killed her immediately.
Answer: In addition, another deleted scene shows that the T-1000 was damaged by being frozen and thawed and was having difficulty maintaining form. He wanted to be sure he wouldn't mess it up.
What's especially odd about the scene is that both examples we gave to help answer this question were actually deleted from the original release. When I first saw this movie in the theater when it was released I had the exact same question, it wasn't until I saw the Special Edition with the deleted scenes reinserted that it made sense.
Answer: It comes down to the difficulty in impersonating someone John actually knows. The T-1000 had failed impersonating someone close to John when he got the name of the dog incorrect. A deleted scene (re-incorporated into the film in the Director's Cut) shows him checking the dog's tag afterwards, so he is aware exactly how he was outsmarted. Keeping Sarah alive is a way to avoid this sort of mistake. She is more useful to him at this point alive. He is not expecting her to endure his torture and he certainly isn't expecting her to be able to fight him afterwards.