What is it?
A spark plug is a device used in a gas fueled internal combustion engine. It is threaded into the cylinder head, and its tip protrudes into the combustion chamber. Its purpose is to create a spark to ignite the air/fuel mixture that keeps the engine running.
How Does It Work?
A spark plug channels the energy from your vehicle's ignition coil across an air gap in the combustion chamber. This spark ignites the compressed fuel/air mixture within each cylinder, and the resulting combustion initiates the engines power stroke.
How Is It Made?
A spark plug is made up of a center electrode, ground electrode, resistor (in most cases) and a terminal stud that are assembled inside a ceramic insulator. This insulator assembly is then inserted into a steel shell that is designed to thread into the cylinder head.
Why Does It Fail?
- Electrode Erosion.
- Fouling.
- Resistor Burnout.
- Material Failure.
What are Symptoms of Failure?
- Check Engine Light.
- Misfire.
- Hesitation.
- Hard Starting.
What Are the Consequences of Failure?
- Poor Fuel Economy.
- Poor Engine Performance.
- Dead Cylinder(s).
- Engine Damage.