What Is An Ignition Coil?

Update:Apr 15,2022
Summary:  The ignition coil is a key component in the ignition system of gasoline vehicles. It is designed to convert the battery's low voltage (12 volts) int......

  The ignition coil is a key component in the ignition system of gasoline vehicles. It is designed to convert the battery's low voltage (12 volts) into the thousands of volts (40k volts) needed to create a spark in a spark plug. This spark is used to ignite the air-fuel mixture during engine combustion.

  There is an ever-increasing demand for modern coils:

  The demand for modern ignition coils is increasing due to the need for higher ignition voltages and limited space in the engine compartment.

  As one of Europe's leading original equipment (OE) suppliers of ignition coils, Valeo masters various designs and offers a product portfolio that includes all ignition coil technologies on the market: wet coils, compact coils (from 1 to 8 output), pencil coil, top plug coil, track coil.

  What is a pencil coil?

  Designed to limit energy loss between the coil and the spark plug, the pencil coil works without an ignition lead. Pencil coils are designed to take advantage of limited space and are usually located above the spark plug. Their compact size allows them to fit directly into the spark plug bore. Pencil coils are available for 2 to 16 in-line cylinders and V-engines.

  What is a rail coil?

  Track coils are assemblies of 2 or 4 ignition modules in a single package. Track coils simplify installation and reduce the material count. If one ignition module is damaged, the entire rail needs to be replaced. Rail coils are available for 3 to 16 in-line cylinders and V-engines. It mounts directly on the spark plug.

  What is a compact coil?

  Compact (or multi-outlet) ignition coils provide one coil for every two pairs of cylinders. For example 2 coils for a 4-cylinder engine and 3 coils for a 6-cylinder engine. and 4 for an 8-cylinder engine, and so on. Its design provides the highest energy density and reduces mass by up to 40% compared to first-generation ignition coils.

  For 4 to 16 in-line cylinders and V-engines

  change distributor

  controlled by the module

  Accessories: Requires ignition wire

  What is a wet coil?

  Wet ignition coils are the first generation of coils used in vehicles. It takes its name from the insulating resin used, which is made from oil. It is always used in conjunction with the distributor and must use ignition leads to connect the wet coil to the spark plug and distributor.

  A very basic transformer

  2 coils, one inside the other


  Liquid Fill Cooling/Insulation

  Conventional, Ballasts and Electronics

  The output is generally up to 18kv

  What is a top plug coil?

  Top plug coils are designed for use when space constraints prevent the use of pencil ignition coils and when high output energy coils are required. The top spark plug is mounted directly on the spark plug, the available position above the spark plug is useful for very powerful coils with high spark energy. For 2 to 16 in-line cylinder and V-type engines.