Spark plugs play a critical role in igniting the air-fuel mixture. Over time, spark plugs can become fouled, worn, or covered in deposits, leading to misfires and poor combustion. Regular replacement is essential for maintaining a reliable ignition system.

The spark plug wires (ignition cables) transmit the electrical current from the ignition coil to the spark plugs. Worn or damaged wires can lead to weak or inconsistent sparks. Technicians inspect the wires and replace them if necessary.

Ignition coils generate the high voltage required to produce a spark at the spark plugs. Technicians may test the ignition coils to ensure they are functioning correctly and replace any faulty units.

In older ignition systems with distributors, the distributor cap and rotor distribute the electrical current to the spark plugs. These components can wear out or develop cracks, affecting ignition performance. Technicians inspect and replace them as needed.

The ignition control module (ICM) controls the timing of the spark and may be integrated with the ignition coil. Technicians inspect the ICM for proper function and replace it if necessary.

These sensors provide crucial information to the engine control module (ECM) for proper ignition timing. Technicians check the sensors for proper operation and replace them if faulty.

In engines with timing belts or chains, proper timing is crucial for the ignition system. Technicians inspect the timing components and replace the timing belt or chain at recommended intervals to prevent potential failures.

Technicians may adjust the idle speed and ignition timing to ensure smooth idling and optimal engine performance.

Technicians use diagnostic tools to identify and address any issues within the ignition system. This may involve scanning the onboard computer for error codes and using specialized equipment to analyze ignition system performance.

Components like the distributor cap, rotor, and ignition wires are inspected to ensure they are in good condition and functioning properly.