* Oxygen sensor: The oxygen sensor monitors the amount of oxygen in the exhaust gas and helps the engine control unit (ECU) adjust the fuel mixture accordingly. A faulty oxygen sensor can cause the engine to run rich or lean, which can lead to a check engine light.
* Spark plugs: Spark plugs provide the spark that ignites the fuel in the engine. Worn or damaged spark plugs can cause the engine to misfire, which can lead to a check engine light.
* Catalytic converter: The catalytic converter helps to clean the exhaust gas by converting harmful pollutants into less harmful ones. A damaged catalytic converter can cause a check engine light.
* Mass air flow sensor: The mass air flow sensor measures the amount of air flowing into the engine. A faulty mass air flow sensor can cause the engine to run rich or lean, which can lead to a check engine light.
* Engine coolant temperature sensor: The engine coolant temperature sensor monitors the temperature of the engine coolant and helps the ECU adjust the engine temperature accordingly. A faulty engine coolant temperature sensor can cause the engine to run too hot or too cold, which can lead to a check engine light.
Additionally, any number of other issues could cause a check engine light to come on, including problems with the fuel system, ignition system, or emissions system. If the check engine light is on, it is important to have the car diagnosed by a qualified mechanic.
Note that the check engine light may not always indicate a serious problem. Sometimes, it can be caused by a minor issue that can be easily fixed.
