1. Oxygen Sensor: The oxygen sensor monitors the amount of unburned oxygen in the exhaust gas and helps regulate the fuel-to-air ratio. When the engine is warm, an inefficient oxygen sensor may cause the engine to run rich or lean, leading to the check engine light turning on.
2. Coolant Temperature Sensor: The coolant temperature sensor measures the temperature of the engine coolant. If this sensor fails or provides incorrect readings, the engine control unit (ECU) can receive inaccurate information, potentially triggering the check engine light.
3. Mass Air Flow (MAF) Sensor: The MAF sensor measures the amount of air flowing into the engine. If it malfunctions or becomes dirty, it can affect the engine's air-fuel mixture, causing engine performance issues and potentially illuminating the check engine light.
4. Knock Sensor: The knock sensor detects engine knocking or detonation, which can damage the engine. When the engine is warm, the increased pressure and temperature can make knocking more likely. A faulty knock sensor can cause the ECU to adjust the engine timing incorrectly, leading to check engine light activation.
5. Camshaft Position Sensor: The camshaft position sensor monitors the position of the camshaft and synchronizes it with the crankshaft's rotation. If this sensor fails or provides inaccurate readings, it can disrupt the engine's timing, leading to engine performance problems and the check engine light coming on.
Remember that determining the exact cause of the check engine light requires diagnostic tools and expertise. It is recommended to consult with a mechanic or use an OBD-II scanner to read and interpret the diagnostic trouble code (DTC) associated with the check engine light for accurate diagnosis and repair.
