1. Oxygen Sensor: The oxygen sensor monitors the amount of oxygen in the exhaust gas and helps control the air-fuel mixture. A faulty oxygen sensor can cause the Check Engine light to come on.
2. Catalytic Converter: The catalytic converter helps clean up the exhaust emissions by converting harmful pollutants into less harmful substances. A clogged or damaged catalytic converter can cause the Check Engine light to come on.
3. Mass Air Flow (MAF) Sensor: The MAF sensor measures the amount of air entering the engine. A faulty MAF sensor can cause the Check Engine light to come on.
4. Coolant Temperature Sensor: The coolant temperature sensor monitors the temperature of the engine coolant and sends this information to the engine control unit (ECU). A faulty coolant temperature sensor can cause the Check Engine light to come on.
5. Vacuum Leaks: Vacuum leaks can cause the engine to run lean, which can trigger the Check Engine light.
6. Spark Plugs and Ignition System: Faulty spark plugs or ignition components can cause the engine to run rough and trigger the Check Engine light.
7. Fuel Injector Problems: A faulty fuel injector can cause the engine to run rich or lean, which can trigger the Check Engine light.
8. EGR (Exhaust Gas Recirculation) System: Problems with the EGR system can cause the Check Engine light to come on.
9. Faulty Knock Sensor: The knock sensor detects engine knocking and adjusts the ignition timing to prevent engine damage. A faulty knock sensor can cause the Check Engine light to come on.
10. Faulty Idle Air Control (IAC) Valve: The IAC valve controls the amount of air that bypasses the throttle body when the engine is idling. A faulty IAC valve can cause the Check Engine light to come on.
To find out the exact cause of the Check Engine light, it's best to have the vehicle diagnosed by a qualified mechanic who can access the vehicle's computer system and identify the specific trouble codes.
