1. Engine Misfires: A faulty spark plug, ignition coil, or fuel injector can cause the engine to misfire, triggering the check engine light.
2. Oxygen Sensor Issues: A malfunctioning oxygen sensor can disrupt the engine's ability to effectively burn fuel, causing a check engine light to come on.
3. Catalytic Converter Problems: A damaged or inefficient catalytic converter can lead to an illuminated check engine light, indicating issues with the vehicle's emissions system.
4. Faulty Emissions Control System: Problems with the vehicle's EGR valve, PCV valve, or other emission control components can also cause the check engine light to illuminate.
5. Loose or Disconnected Gas Cap: A loose or improperly tightened gas cap can also trigger the check engine light because it can affect the vehicle's fuel evaporation control system.
6. Faulty Sensors or Switches: Various sensors and switches throughout the vehicle, such as the mass airflow sensor, camshaft position sensor, or throttle position sensor, can malfunction, causing the check engine light to come on.
7. Computer Problems: Issues with the vehicle's engine control module (ECM), commonly referred to as the "computer," can also result in the check engine light illuminating.
To accurately identify the cause of the check engine light in your 2002 Mazda Protege, it's recommended to have the vehicle diagnosed by a professional mechanic or an automotive service center.
