Shadow Raiders as per this answer. It's a Canadian show that ran from 1998 to 1999 that featured computer animation and planets with secret stardrives built into them.
Shadow Raiders is set in a five-planet solar system known as the Cluster. The four habitable planets are in a constant state of war, always raiding one another for resources unique to each planet. However, when an alien named Tekla comes from another solar system, she brings a warning: the Beast Planet is coming. Now Graveheart, a humble miner of Planet Rock, must convince the leaders of Fire, Rock, Bone, and Ice to put aside their differences and stand together against the Beast, their new common enemy.
The main setting of Shadow Raiders is the Cluster, a series of four interdependent worlds. The four main planets — Fire, Rock, Bone, and Ice — have warred for as long as any of them can remember over their natural resources: Fire produces energy, Rock produces metals and minerals, Bone produces food, and Ice produces water, and all four worlds depend on each other to survive.
A large part of the series mythology in the second season is the World Engines, a propulsion system built into the planets of the Cluster (and presumably many other worlds, since two different planets in different solar systems have them) by an ancient alien race. Using five mountain-sized energy thrusters which emerge from the planet's surface, the World Engines can propel a planet through space at great speeds. A combination of an atmospheric shield and artificial gravity generators keep the sudden shift in orbit and lack of a star from killing everyone on the surface. The Prison Planet has a variation known as Teleport Engines, which teleport the world to different locations in space instantly. The same artificial gravity and atmospheric shielding technology is used to protect the inhabitants. Each set of engines is located at the core of its world and can be reached using Telepods, small platforms on the surface of each world. The Telepods send the user to the core of the planet where they can use the computer to move the planet. The Telepods can also be used to move people from one planet to another.