Your vehicle's engine is full of moving parts, and those parts require oil to move properly. Since the oil breaks down with use, an oil change is necessary. You will be told when to bring the car back in for another oil change, which is usually within a few months or 3,000 miles. If you do not get an oil change periodically, your engine will not perform as well. Its parts will eventually warp and wear out when you do not maintain your oil change schedule, and your check engine light may come on.