Cars require maintenance, and good timely maintenance at that. To get the maximum amount of life out your ride, things like oil changes, tire rotations, valve services, and other easily overlooked bits of maintenance can't be forgotten. But even with good regular service, an engine doesn't last forever. Metals warp from heating and cooling, accidents happen, and components just wear with age, and thus they lose power. How much could your car change after twenty years have come and gone?
