Few things are more frustrating than seeing the check engine light turn on while you’re driving. It’s a warning that something isn’t right under the hood, but the cause can range from a minor issue to a major problem that requires immediate attention. Because modern vehicles rely heavily on sensors and computerized systems, the light can turn on for a variety of reasons. At A-1 Automotive, our local mechanics provide expert check engine light diagnostics and repair in the greater Portland, OR area. Here’s a look at four issues that commonly cause the check engine light to illuminate. Faulty Oxygen Sensor The oxygen sensor monitors how much unburned oxygen is in the exhaust and helps regulate the engine’s air–fuel mixture. When it starts to fail, fuel-efficiency drops and emissions increase. Left unaddressed, it can even damage the catalytic converter. Replacing it early helps your vehicle run more efficiently and prevents bigger repair costs. Failing Ignition Coils or Spark Plugs Ignition coils and spark plugs play essential roles in powering your engine. When either one fails, the engine may misfire, run rough, or lose power. Misfires are a major trigger for the check engine light because they contribute to poor engine performance. Replacing faulty coils or plugs can restore smooth performance. Catalytic Converter Problems Your catalytic converter helps reduce harmful exhaust emissions, but when it becomes clogged or begins to fail, it can cause major significant issues. A failing converter often leads to reduced power, poor fuel-economy, and a persistent check engine light. Because of the catalytic converter’s important role, issues with it need to be addressed ASAP. Mass Airflow Sensor Issues The mass airflow sensor measures how much air enters the engine so the computer can inject the right amount of fuel. When it malfunctions, the engine may hesitate, stall, or idle poorly. A bad MAF sensor is a frequent cause of check engine warnings. Check Engine Light Repair in Portland, OR For expert auto repair in Portland, OR, or Vancouver, WA, visit A-1 Automotive. Feel free to give us a call to schedule an appointment!