Sorry if this posts twice.  The movie I need the name of had a mom whose daughter (I think) had been kidnapped.  There was a psycho guy making her drive different places, and he knew everything she was doing.  I for sure remember her getting pulled over by a cop.  She passed him a note on yellow paper (I think if she talked the guy could hear her).  All of a sudden a car came and plowed down the cop.  The guy must have hacked into other cars too.  Sorry, this is so sketchy…