Every explosion needs an ignition source, and within many types of (mostly gasoline) combustion engines, the source is the spark which jumps from the tip of a spark plug.
The plug is a component which forces electricity to jump from one point to another within the combustion chamber, which ignites the air and fuel within the chamber.
Spark Plug Design by Cars Simplified
Spark plugs explained with up close visuals!
Alternative Spark Plug Types
Most spark plugs are the conventional gap spark type, but there are alternative ways to ignite an air/fuel mix.
Laser
Instead of having electricity jump a gap, a laser can be shot between a gap to achieve the same igniting effect, but more efficently and over a greater distance. However, actual laser ignition is not to be confused with laser-welded conventional spark plugs, which often have "laser" in their branding/name.
Plasma
Plasma, or corona spark plugs, are much more powerful and effective than either traditional or laser spark plugs. It shoots jets of plasma into the combustion chamber, quickly igniting all the fuel. Plasma spark plugs may slightly change engine behavior (since the fuel is completely burned up sooner) and improve fuel efficency.
- AC Delco
- Accel
- Autolite
- Bosch
- Champion
- Defiance (Former)
- Denso
- E3
- Firestone (Former)
- Motorcraft
- Multispark
- NGK
- Pulstar
- Splitfire
Companies that Produce Spark Plugs
Counterfeit Spark Plugs by Torque Test Channel
Torque Test Channel buys sets of spark plugs from multiple sellers and compares legitimate versions to counterfeits.