Why is the engine fault light on?

[LeCharlotte]

The reasons for the engine fault light being on are: 1. Sensor malfunction; 2. Maintenance issues; 3. Poor combustion of the air-fuel mixture; 4. Poor fuel quality; 5. Dirty air filter. Solutions for the engine fault light being on include: 1. Disconnect the negative terminal of the engine battery, wait for 30 seconds, and then reconnect it; 2. Go to a 4S shop for inspection. Precautions for engine maintenance are: 1. Regularly change the engine oil and filter; 2. Regularly maintain the air filter; 3. Regularly replace the fuel filter; 4. Regularly maintain the radiator mesh; 5. Regularly replace the spark plugs.

[ManuelRose]

Having driven for so many years, I've encountered the engine warning light coming on several times, with quite a few main causes: first, sensor issues, like inaccurate oxygen sensor readings, or faults in the intake air temperature or mass airflow sensors, which the ECU detects as abnormal and triggers the light; second, problems with the emission system, such as a clogged or inefficient catalytic converter, which is quite common; then there are ignition system problems, like worn spark plugs or short circuits in the ignition coils affecting ignition, leading to unstable engine operation; also, fuel system troubles, such as clogged fuel injectors or insufficient fuel pump pressure, causing uneven fuel injection and naturally triggering the warning; exhaust leaks or cracked vacuum tubes can also set it off. Don't underestimate this light—when it comes on, it indicates reduced performance, increased fuel consumption, and even potential for more serious damage like engine overheating, so it must be addressed immediately. Using an OBD scanner to read the fault codes and identify the source is the easiest way; if you don't have the tools, head to a professional repair shop right away. Don't let it escalate into a bigger issue—maintaining your car's health is crucial.

[StSophia]

When the engine malfunction light flashes while driving, it always makes me nervous! It usually lights up because the onboard computer detects issues: failed sensors like those measuring oxygen or temperature; ignition system defects, such as aging spark plugs failing to ignite; fuel system malfunctions, like poor fuel injection or abnormal oil pressure; emission system problems, such as a clogged catalytic converter; or even vacuum leaks. Ignoring it can lead to poor performance, increased fuel consumption, and even the risk of stalling on the highway. My advice is to take immediate action: visit a repair shop to use diagnostic tools to read the error codes and accurately identify the cause for repair. From personal experience, regular maintenance like replacing filters and checking sensor connections can reduce the chances of the light coming on, making driving safer and more worry-free.

[DeCora]

When the engine malfunction light comes on, the ECU is alerting you to a system anomaly. Common causes include sensor failure, emission system issues, or ignition/fuel system faults. Simply put, something isn't operating normally, and the computer detects it, triggering the warning light. This should never be ignored, as it can lead to reduced engine performance, increased fuel consumption, or even more serious problems. It's recommended to visit a repair shop immediately to read the diagnostic trouble codes (DTCs) for accurate diagnosis, or use an OBD scanner yourself for targeted repairs. Avoid driving long distances with the light on - prioritize safety and cost-effective maintenance.