Megas XLR (2004)

In the future, humanity has been beset by a horde of alien invaders. Kiva, a human soldier, has captured an alien mecha, the Megas, and remodeled it, planning to send it back in time three years to a pivotal battle so that the humans can win the war. Her plan goes awry when the Megas is fired upon in transit, rocketing it at random through time. She pursues it, as does the alien mothership. Curtain up on present day. A slob in New Jersey has discovered the Megas in a pile of garbage. Kiva, having caught up to him, is dismayed to learn that it has been remodeled, its head replaced by a classic muscle car, its controls integrated with video game controllers, making her new (and unfortunate) ally, Coop, the only one capable of piloting the Megas. She must now find a way to repair the Megas' time controller and return to the future, as well as dealing with the various challenges inherent in co-owning the Earth's most destructive piece of hardware... especially since Coop insists that it is HIS robot, and seems to be somewhat judgementally impaired.