What does it mean when the engine light on the dashboard is on?
2 Answers
Generally, when a malfunction indicator light is illuminated, it indicates that the component being monitored by the light has detected an abnormality. Below are some possible reasons why the engine light might be on: 1. The oxygen sensor detects the oxygen concentration in the exhaust gases and sends this information to the ECU in the form of an electrical signal. The ECU then uses this data to control the fuel injection amount. If the oxygen sensor is damaged, it will inevitably affect the air-fuel ratio of the mixture, thereby impacting the engine's normal operation. The air flow meter senses the intake air volume and relays this information to the ECU, which then controls the fuel injection accordingly. If the ECU cannot receive this information, the engine malfunction light will also illuminate. 2. If low-grade gasoline is used or the engine temperature becomes excessively high, it can lead to engine knocking. Engines are equipped with knock sensors, and when the sensor detects a tendency for knocking, the ECU will attempt to mitigate it by delaying the ignition timing. However, if the issue exceeds the ECU's capacity to handle, the engine malfunction light will turn on. 3. Solution: If the engine malfunction indicator light comes on, it is important to seek timely inspection and repair.
I've been driving for over a decade, and the engine light on the dashboard is a common occurrence—no need to panic, but it should be taken seriously. The most frequent issue is sensor problems, like an aging oxygen sensor or excessive carbon buildup, which can make the car mistakenly think emissions are exceeding standards. It could also be a loose fuel cap, allowing air to leak in and triggering the system alarm. Ignition system failures, such as worn spark plugs, can also cause the light to come on, especially if accompanied by engine shaking or increased fuel consumption. Last time I encountered this, I first plugged in an OBD scanner to read the fault codes—that little port in the car—and found it was an issue with the mass airflow sensor. Cleaning it resolved the problem. If the light stays on, get to a repair shop immediately. Delaying could damage the catalytic converter, and that’s an expensive fix.
