While the plot doesn't exactly match your description, it features a powerful, mysterious, and seemingly sentient car that terrorizes a small town. The car was created by a brilliant inventor who is later murdered, leaving the car to wreak havoc. The film does touch on themes of corporate greed and government interference, although it focuses more on the car's sinister nature.
Let me know if this sounds familiar, or if you have any other details about the film you're thinking of. I'd be happy to help you find it!