Theory. If you decide to buy a used foreign car and have chosen a specific model, try to collect as much information about it as possible in advance. The best way to do this is to inspect a similar model in a showroom that sells new cars. First of all, find out where the identification number (VIN) should be located. The car may have additional VIN stickers (are made as transfer pictures), - find out where they are located.
Practice. So, you start inspecting the selected car. It is worth starting with checking the condition of the paintwork near the identification numbers. It should not differ in color and texture from the coating on the inside of the trunk, hood, engine compartment. Soft surface (there remains a trace of deformation even from a nail), paint drips and uneven application - all this indicates that the place where the identification number is located has been repainted. And repainting hides either the consequences of an accident or traces of a change in the number. The coating near the number can be rubbed with a swab soaked in solvent: if the paint dissolves at least partially, this is a sure sign that it is "not original".
Now about the numbers and identification plates. If the number is re-punched, the characteristic signs of this operation remain: the metal surface is most often deformed, slightly convex or concave. With a homemade method of re-punching, a double outline is often noticeable; the signs are not on the same line, but "jump", they have different depths of indentation; between letters or numbers - intervals of different sizes. Pay special attention to identical signs. They should not differ from each other in shape or size. Another important point: if you notice any characteristic feature on identical signs in the numbers - be sure that these signs are not factory. The company number is applied with a single stamp, the "artisan" uses a separate stamp for each number or letter and repeats the characteristic "mistake".
It is more difficult to detect a "criminal" car when the number has been replaced together with the part or part of it on which it is stamped. As a rule, in this case the number is the factory number. Therefore, it is necessary to inspect the places where this part is attached to the body. A simple way to detect such a replacement can be tapping. You should be wary if the sound when tapping is dull, "wooden" or rattling. It is worth remembering that in cars, individual parts of the body are attached using contact welding. The joints are usually points with a diameter of 5-6 mm. If there are traces of another type of welding in the places where the "numbered" part is attached to the body, and their surfaces are also deformed, then the part is not attached to the body in the factory way.
When inspecting the engine, pay attention to the platform with the number: it should be flat, and the signs on it should be clearly and brightly stamped, without double contours. By the way, the platform itself is turned on a milling machine, which leaves traces in the form of semicircles. They are clearly visible even with severe corrosion.
[Original published on the website: www.mercedesman.ru]
The described signs are quite easy to detect even for a non-professional. There are others, but they can only be detected by specialists. It is worth contacting them if you have any doubts.