1. Ignition Switch Activation: Turning the key to the "start" position completes an electrical circuit in the ignition switch.
2. Starter Motor Engagement: This circuit energizes the starter motor, a powerful electric motor geared to the engine's flywheel.
3. Flywheel Rotation: The starter motor spins the engine's flywheel, a heavy rotating disc.
4. Engine Cranking: The flywheel's rotation, coupled with the compression of the air-fuel mixture in the cylinders, attempts to start the engine's internal combustion process.
5. Combustion Ignition: Once the engine's speed reaches a certain point, the spark plugs ignite the compressed air-fuel mixture. This creates a controlled explosion that pushes the pistons, resulting in engine rotation.
6. Starter Motor Disengagement: Once the engine is running and self-sustaining, the ignition switch (or a mechanism within it) disengages the starter motor. This prevents damage to the starter motor from the high engine speed.
7. Electrical System Activation: The engine's rotation drives the alternator which recharges the battery and provides power to the car's electrical system.
If the car doesn't start, it could be due to a variety of reasons, including a dead battery, a faulty starter motor, problems with the ignition system (spark plugs, wires, distributor), fuel delivery issues, or engine mechanical problems.
