What is an ignition coil and what does it do?

December 20, 2022

How does an ignition coil work?

The core of the ignition coil is made of laminated soft iron, around which the device is built. There are two coils made of enameled copper wire wrapped around the core. Coil one features a thick wire with few windings, while coil two has a thin wire and many windings. There is insulation paper between these wires, which prevents short circuits. For the little device to work, it has a DC voltage input. This ensures that the electrons can only go one way. This DC voltage is only 12 volts, but with the thick wire, voltage between 15,000 and 25,000 volts is generated. This voltage goes to the spark plug, which thereby sparks and ignites the fuel.

Replace

The ignition coil, of course, can break down. Fortunately, you can replace it yourself. We’ll explain exactly how. You start by shutting off the power to prevent accidents. Disconnect the battery and make sure at least one wire is not connected to the battery. Next, remove the canopy. You may need special tools for this, but that depends on the cover the coil has.

Ignition coil type

Now it’s time to disassemble the ignition coil. You need to determine which type of ignition coil you have, as there are three. The difference between ignition coils is the connection. With the smallest coil, it is easy to get it loose by unscrewing it and removing three leads. The second type of coil is also easy to get loose. This is because it is connected to the system by a plug. If you disconnect this plug including cables you can remove the ignition coil. The third type of ignition coil is more difficult to remove because it serves multiple spark plugs and cylinders. If you want to remove it you have to be very careful that you also remove all these cylinders and spark plugs and take out the ignition coil as a whole.

New places

Once the old coil is out, you can install the new one. Do this in exactly the same way the old ignition coil was attached. After this, replace the canopy and reconnect the battery. Can’t you do this yourself? No stress, then have your garage replace the ignition coil. This will generally cost you between 100 and 200 euros per coil.