What does 'Check Emission System' mean?
2 Answers
Check Emission System indicates a malfunction in the engine's emission system, where the engine is running poorly and the exhaust emissions do not meet standards. This system monitors the condition of the engine's air-fuel mixture through oxygen sensors. When the mixture changes, leading to excessive exhaust emissions, the control unit records the fault and stores it, thereby illuminating the warning light to alert the driver. Here are the detailed explanations: 1. The occasional illumination of the exhaust emission system warning light is mostly due to substandard fuel quality. If the exhaust emission light remains on continuously, it is necessary to use diagnostic equipment to check the fault storage in the engine and proceed with step-by-step troubleshooting. All sensors, wiring, and actuators (motors and solenoid valves) related to the combustion of the air-fuel mixture in the engine should be inspected. 2. Problems with the control unit and other components can cause the engine exhaust emission fault light to illuminate. Common causes include a dirty throttle body, and carbon buildup on the valves and fuel injectors.
This warning usually means the yellow engine light on the dashboard is illuminated, right? I was also confused when I encountered it last time. Simply put, there's an issue with the vehicle's exhaust treatment system that needs immediate attention. It could be a minor problem like a loose fuel cap, or something more serious like a faulty oxygen sensor or an exhaust system leak. Don't underestimate this small warning light—ignoring it can lead to a sharp increase in fuel consumption and definitely cause you to fail the annual inspection. I once delayed dealing with it for half a month and ended up spending over 2000 yuan more on repairs. My advice is to first check if the fuel cap is tightened properly. If the light remains on, quickly take it to a repair shop to read the fault codes—don't wait until major problems arise like I did.
