Where is the car ignition coil located?
2 Answers
The car ignition coil is positioned at the front upper part of the engine. Inside the ignition coil, there are two sets of windings: the primary coil and the secondary coil. The primary coil is wound with approximately 200 to 500 turns of enameled wire about 0.5 to 1 mm in diameter, while the secondary coil is wound with around 15,000 to 25,000 turns of enameled wire about 0.1 mm in diameter. The working principle of the car ignition coil is as follows: 1. When the primary coil is connected to the power source, a strong magnetic field is generated around it as the current increases, and the iron core stores the magnetic energy; 2. When the switching device disconnects the primary coil circuit, the magnetic field of the primary coil rapidly decays, inducing a high voltage in the secondary coil; 3. The faster the magnetic field of the primary coil disappears, the larger the current at the moment of disconnection, and the greater the turns ratio between the two coils, the higher the voltage induced in the secondary coil.
The position of the ignition coil is crucial for vehicle operation, and I often pay attention to this point during car repairs. In most modern vehicles, the coils are directly installed above each spark plug, commonly known as the coil-on-plug system; older cars may have them concentrated near the distributor on top of the engine. The design considers thermal management and vibration, typically securing them to the engine block to prevent overheating or loosening that could cause malfunctions. If the coil is displaced or poorly positioned, it can lead to misfires, rough idling, or difficulty starting, in which case it's necessary to check if the fasteners are intact. Related topic: The coil converts low voltage to high voltage, and its proximity to the ECU interface ensures signal transmission. It's recommended to regularly clean surrounding dust to avoid cooling issues and extend the coil's lifespan. Identifying their location is simple—open the hood, and they are usually black square-shaped components connected to the spark plug wiring harness.
