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The spark plugs are an important part of the ignition system. When you turn the ignition key (car's key) on, it causes the ignition coil to generate the spark which ignites the air-fuel mixture in the engine cylinders to start the engine. The number of spark plugs in the car is the same as the number of cylinders, although some vehicle manufacturers will use two spark plugs per cylinder.
Over time, the spark plugs wear out and require replacement. When the spark plugs wear out, it is harder for it the air-fuel mixture to ignite, resulting in engine misfires. If one of the spark plugs has failed, the car will still start and run, but it will run poorly. On some vehicles, spark plug replacement may be labor intensive and involve removal of the intake plenum.
During routine maintenance and checkups, your ignition system should always be inspected. Any time that a component of the ignition system is replaced, it’s a good idea to consider replacing the spark plugs as well. If you don’t preemptively change your spark plugs your engine will let you know by misfiring or running poorly, so schedule an inspection as soon as you notice that your engine is not performing properly.
Spark plugs are responsible for igniting the fuel that your engine uses to run. When you turn your key, a small voltage of power is sent to the ignition coil, where it is transformed into high voltage currency. This high voltage currency is sent through the ignition cables to the spark plugs. The spark plugs use the power to create a spark, which ignites the fuel, and allows the engine to function.
When the spark plugs malfunction, this spark won’t be created, and the fuel will not be ignited as it should. Your vehicle has many spark plugs, so depending on how many fail, your engine may either run poorly, or not run at all. Continuing to drive a vehicle with malfunctioning spark plugs can also cause damage to the catalytic converter.
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