• Oxygen sensor failure: The oxygen sensor measures the amount of oxygen in the exhaust gas and helps the engine control unit (ECU) adjust the fuel mixture accordingly. If the oxygen sensor fails, the ECU will not be able to properly adjust the fuel mixture, which can lead to engine problems and the check engine light coming on.
• Mass airflow sensor (MAF) failure: The MAF sensor measures the amount of air entering the engine and helps the ECU calculate the amount of fuel to inject. If the MAF sensor fails, the ECU will not be able to properly calculate the amount of fuel to inject, which can lead to engine problems and the check engine light coming on.
• Spark plug failure: Spark plugs provide the spark that ignites the fuel in the engine. If one or more spark plugs fail, the engine will not be able to run properly, which can lead to engine problems and the check engine light coming on.
• EGR valve failure: The EGR valve (exhaust gas recirculation valve) recirculates a small amount of exhaust gas back into the engine to help reduce emissions. If the EGR valve fails, it can cause engine problems and the check engine light coming on.
• Faulty catalytic converter: The catalytic converter helps to reduce harmful emissions from the engine. If the catalytic converter fails, it can cause engine problems and the check engine light coming on.
If the check engine light comes on in your 2004 Mercedes-Benz C230, it is important to have the car diagnosed by a qualified mechanic to determine the cause of the problem and have it repaired as soon as possible.
