Comet passes too close to Earth, awakening all manner of mechnical devices, especially cars & trucks. Unfortunately for humans, they don't have very good intentions.
Loosely based on Stephen King's short story "Trucks," and also directed by him, this certainly isn't in any way a classic. It is, however, well aware of its B-movie status, and remains a cheerfully watchable slice of 1980s cheese. There is some wit on display (the ice cream truck playing "King of the Road," for example) but most of it is lost amidst said cheese. And a little less of Yeardley Smith would have been nice. . .Still, there are a lot worse Stephen King movies out there (cough, Graveyard Shift, cough)!
Gas is like 89 cents a gallon in this film, a fact more frightening than anything seen on screen. Hmmm. . .