How Many Digits Does an Engine Number Have?
2 Answers
Common engine numbers typically consist of 7-8 digits. The sequence and content of engine numbers may vary among different manufacturers. Generally, it includes the engine model, production date, and a randomly assigned serial number given when the engine comes off the production line. Some may also include a place-of-origin code. Engine model is an identification code assigned by the engine manufacturer in accordance with relevant regulations, corporate or industry practices, and engine attributes. It represents information such as the manufacturer, specifications, performance, features, technology, purpose, and production batch of the engine, including fuel type, number of cylinders, displacement, and static braking power, among others. Engines installed in passenger cars or multi-purpose passenger vehicles are required to display the professional manufacturer, model, and production number of the engine. It is important to note that the engine number is not the same as the engine model. The engine model refers to the specifications and size of the engine within the manufacturer's product line, and multiple engines can share the same model. The engine number, however, refers to the production number of the engine, where each engine is assigned a unique number that differs from all others. Structure of an Engine Number: Front Section: Includes product series code, generation symbol, and regional or corporate code. Manufacturers may choose appropriate letters as needed, but these must be approved and recorded by the industry standardization authority. Middle Section: Composed of symbols representing the number of cylinders, cylinder arrangement, stroke, and cylinder diameter. Rear Section: Consists of symbols indicating structural features and usage characteristics. Tail Section: Distinguishing symbols. When differentiation is needed due to improvements or other reasons within the same product series, manufacturers may select appropriate symbols. The rear and tail sections can be separated by a hyphen.
When I first dealt with this, I realized the engine number digits aren’t fixed—typically ranging from 6 to 10 digits, but it varies by model. Older cars might have just 6 pure digits, while newer ones mix letters, making them longer. You’ll usually find it on the plate under the hood, but you may need to clean off dust to read it clearly. The digit count is crucial for buying or transferring ownership, as traffic authorities strictly verify it to prevent tampering. For example, my friend’s used car had a slightly damaged engine number and was outright denied registration. Mechanics advise regularly checking the digits’ integrity during maintenance to prevent theft or accident risks. Before buying, photograph key numbers as backup to avoid hassles. Bottom line: don’t guess the digit count—actual inspection is the only way.
