What is the engine number for the BMW 523?
3 Answers
The engine number for the BMW 523 is located on top of the left and right shock absorbers in the engine compartment. It is generally a combination of 7 to 8 digits and letters. In addition to the above method, the engine number can also be checked in the following 4 ways: The vehicle's driving license displays the engine number, usually found on the second-to-last line; The motor vehicle registration certificate will indicate the engine number; The car purchase invoice will specify the engine number; The vehicle purchase tax payment certificate will indicate the engine number. 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, and engine models can be the same. The engine number, however, refers to the production number of the engine, where each engine can only have one unique engine number, and no two engines share the same number.
As someone with some knowledge of automotive mechanics, I can tell you that the common engine model for the BMW 523Li is the N52B25, a classic inline-six engine from BMW with a displacement of approximately 2.5 liters. The specific location of the number is usually on the engine block near the firewall or clearly printed on the vehicle's nameplate. I remember a few years ago when helping a friend repair their car, I realized it was essential to verify this number because models from different production years, such as those between 2006 and 2010, might have minor adjustments but are fundamentally the same. In practical use, this number is crucial—for instance, when purchasing filters or spark plugs, you must ensure they match; otherwise, performance will suffer after installation. If you're unsure about your car's specifics, the simplest method is to check the registration details on the vehicle's license or consult a 4S dealership; they can quickly confirm it by checking their system. If you're handy, pop the hood and use a flashlight to inspect the engraved area—it should take less than five minutes. Avoid carelessly noting the wrong number, as it can lead to delayed repairs, wasting both time and money.
I previously drove a BMW 523Li, which was the 2009 model. I clearly remember the engine number being N52B25. Before every maintenance session, I had to check the nameplate, which is located below the side of the passenger door or on that small metal plate inside the hood. Personal experience tells me that technicians at the 4S shop also prioritize confirming this number; otherwise, the wrong parts can make the car feel sluggish. I suggest you check the vehicle license directly for the easiest solution, saving you the trouble of crawling under the car. Memorizing the number is beneficial for daily maintenance—like when I change the oil, reporting the number in advance ensures accurate part ordering. If the vehicle is too old or a newer version, there might be changes, but the old 523 generally sticks with this engine model. Make it a habit to save a photo of the number on your phone as a backup. In case of a breakdown on the road, sending the picture to the repair shop gets things started immediately.
