My issue with the ending(obvious spoiler)
Throughout the first film, and 99% of this film Harry is not a vigilante. He's a cop who pushes the envelope, doing things he shouldn't do, according to the rules, but should do according to his sense of justice. But at the end, he sets the timer on the bomb and tosses it into the backseat of the car, killing Hal Holbrook when it explodes. At that point Harry wasn't in any danger. This seems a violation of his code of justice. Shooting Scorpio in the stadium in the first film might seem unnecessary, but you can make a case that he didn't want him to get away, delaying the anticipated rescue of the girl. But there was no reason for him to kill Holbrook's character, other than vigilantism, which he was opposed to.
"My girlfriend sucked 37 d*cks!"
"In a row?"