All cars have serial numbers stamped into them in numerous different places, called the VIN (Vehicle Identification Number). This uniquely identifies the car much like DNA for humans. The VIN will be put in a couple of places, some obvious (e.g. on a metal plate just under the windshield) and some hidden (e.g. on the engine). Other places include: On the door frame/door post of the front doors (usually driver's but sometimes passengers), on the steering wheel/steering column and on the radiator support bracket. You can sometimes find out on the internet where all the VINs are for your particular make of car.

To make the car untraceable, you need to get rid of these VINs and the license plates. This is not easy, as serial numbers can often be restored depending on the technique used to deface them. VINs on metal are stamped in, altering the crystal structure of the metal. Filing or grinding does not change this, and the serial can be revealed by chemical etching. Instead, you should file it down until the numbers are not visible, and then hammer on it until you create a clear indent where the numbers were. Hammer in nails and other pointy objects to create new dents over the top of the original numbers.

VINs on plastic and car engines are usually heat treated to reveal the number. If possible, just remove that piece of plastic. If this is not possible, heat that area with a blowtorch, and once it starts to glow/melt, bash it with a hammer until the numbers are not visible. This is probably not possible with an engine – so just buy a new one.