Why does the engine light stay on yellow but everything seems normal?
2 Answers
If the engine light stays on yellow but everything seems normal, it might just be a sensor malfunction or a false alarm. If the owner notices that the engine light stays on yellow but everything appears normal, they can try repeatedly starting and turning off the car three times in a row, or disconnect the negative terminal of the car battery, wait for 30 seconds, and then reconnect it to check if it's a false alarm issue with the engine. Reasons for the engine light to come on: 1. Excessive carbon buildup inside the engine, leading to poor gasoline atomization, damaged oxygen sensors, or incomplete combustion of gases in the combustion chamber; 2. Damaged spark plugs, causing engine misfires and insufficient power; 3. Damaged components of the car's exhaust system, such as oxygen sensors or the catalytic converter, leading to non-compliant vehicle emissions; 4. Overheating of coolant or oil temperature.
I've been repairing cars for years and have seen many drivers complain about the engine yellow light being on but the car feels fine to drive. This situation is usually caused by minor fault codes, with the most common being sensor failures, such as the oxygen sensor or temperature sensor sending incorrect signals, causing the computer to record an error but the car still runs. It could also be due to a loose fuel cap causing emission issues, or unstable signals from poor wiring connections. However, you should take this light seriously—it's essentially an early warning system. Ignoring it for a long time can quietly affect fuel consumption or engine efficiency. I recommend buying an OBD scanner to read the codes yourself—it's not expensive—or simply take it to a repair shop for diagnosis. Don’t assume it's nothing and delay fixing it. If it turns out to be excessive emissions or a buildup of minor issues, repairs could become more expensive later. Regular checks can prevent problems before they escalate.
